Here's a challenge I thought off, which I think it's an interesting as I haven't seen anything close to it. There are rules that require a certain expansions pack to be installed, which I do recommend having at least one of them, for the full experience of the challenge. If you don't have an expansion that requires or related to follow a certain rule, you may skip its defined restrictions.

As with any challenge, you may add or modify it to your liking for the sake of your enjoyment of playing. You may even provide me with your ideas on how I can expand it further or what tweaks it needs If something is flawed, broken or impossible to achieve within this challenge. Also, it might work well to incorporate any other challenge that don't conflict with this one.


INTRODUCTION
Start off with a new empty unpopulated neighborhood. Reside as many families as you'd prefer.

Since this the town/city/village/whatever was just founded, the challenge will start with the first generation of people. The Second gen once a new sim gets born, who will be classified of that generation. Those that are born from CAS (Create-A-Sim) will belong to the oldest generation that still remains alive. If that in-game born generation dies, the future CAS sims will be classified to the next one.

Ok, so: the First generation start off with very cheap plumbing amenities, candle-lit lights (electricity has yet to be invented), the very cheap refrigerator. Utilities that are allowed are dining tables with chairs, shelter (a simple details: more details below ), instruments that run without batteries (i.e. violin, drums (only after topping Music career), piano) and easel, crafting benches and stations. Get rid-off Rod Humble's package without opening it or keep it in/on the inventory/ground until the said object is unlocked when the objective is reached which you then can open the present.

UNLOCKING STUFF

REGARDING BADGE
Flower Arranging & Pottery
* As the sim progress in flower arranging talent, it unlocks more indoor-plants with bigger environment score than before respectively.
** Bronze for 3-4 plants of environment score, silver: 5-6, gold 7-10.
* As the sim progress in pottery talent, it unlocks more deco with bigger environment score than before respectively.
** Bronze for 3-4 plants of environment score, silver: 5-6, gold 7-10.

Robotics
* Once one of the residents of the neighborhood acquires the bronze badge, the challenge will unlock simple yet handy electronics: (alarm) clocks, burglar alarm (with the condition that there are law enforcement team), fire detector (with the condition that somebody has learned fire safety), game consoles, remote control toy car, Treadmill, exercise bike, toaster oven, coffee machine.
* When the silver badge is attained, the new inventions will be included as unlocked: cellphones & telephones, mp3s, handheld game players, tvs, stereos, remote control toy helicopter, microwave, food processors, dishwashers and trash compactors.
* Last but not least, reaching the gold talent badge will grant access to computers and ovens.

Sewing
* Bronze: lowest enviroment score curtains & need score pet beds.
* Silver: medium enviroment score curtains & need score pet beds.
* Highest highest and higher enviroment score curtains & need score pet beds.

Toy Making
* Bronze: Toyboxes, activity tables, monkey bars, slides, pet toys.
* Silver: swings, merry-go-rounds, balloons, spring riders.
* Gold: toy ovens, playground towers, garden sprinklers.

FOOD STOCK
Refrigerators
Ok here's the thing for this challenge: you're not allowed to repurchase a refrigerator or get a new one for the sake of it to restock. You can only restock the fridge with goods by having your sim stock it with their own/someone's grown and fished produce or purchasing a grocery basket through any means (over the phone or travelling to the store), with the latter requiring some criteria to be met to allow you to act upon such alternative:
* To establish a grocery shop/store, let it be purchased or un-owned, there '''must''' be at least one lot with a garden-farm or situated in the town/neighborhood.
* Grocery/Food Delivery service will '''only''' be unlocked once a grocery store/shop or plant/fish market (which is essentially plants/fish that are put on sale in a sim-run business) is established in the neighborhood.

Pizza and Chinese Food
* These special meals can only be unlocked once a restaurant of any kind opens up in the neighborhood.
** You may not activate a munchie bot (if your household happens to have one) until there's a restaurant lot in place and sight within the neighborhood.

FURNITURE
Reaching the corresponding milestone of the neighborhoods generation unlocks the following items:
*5th Gen: full-size refrigerator.
*10th Gen: Living/Arm Chairs & Countertops/Islands.
*15th Gen: Lightbulbs
*20th Gen: Recliners/Lounges & End Tables.
*30th Gen: Sofas/LoveSeats & Coffee Tables.
*40th Gen: Shelf.

Regarding Plumbing, I suggest you have it so that with every new generation being passed on you get to unlock more and more expensive items. Perhaps add a rule that once you attain all the shower/tub objects, you get to unlock hot tubs.

Or you can choose however you would like to progress in unlocking this item. I don't like enforcing my playstyle, so don't think this is exact order you have to follow.

TOPPING CAREERS
You unlock the following objects when topping specific career related to that item:
*Athletic: ElectroDance Sphere.
*Business: Ticket Machine.
*Culinary: BBQ.
*Science: Telescope.
*Slacker: DJ booth and Buffet table.
*Entertainment: Microphone Stand.
*Music: Drum set.
*Oceanography: AquaBox "60 Gallons of Awesome" Aquarium.

ARCHITECTUAL OBJECTS
Half of the objects and building tools are locked, that can be only unlocked after reaching the top career of Architecture career. These include:
*Columns.
*Elevators.
*Foundations.
*Stairs & staircases.
*Swimming pools.
*Windows.

SERVICES
*Gardeners are unlocked once somebody in the neighborhood masters the garden talent.
*Maids are unlocked once somebody in the neighborhood max out the cleaning skill.
*Nannies are unlocked once somebody in the neighborhood learns the parenting skill completely.
*Repair(wo)men are unlocked once somebody in the neighborhood max out the mechanical skill.
*Butlers are unlocked once somebody in the neighborhood gets qualified for all the above duties (for a gardener, maid, nanny and repairman).
*Gypsy matchmakers are unlocked once somebody in the neighborhood learns the couple counseling skill completely.
*Fire Department is unlocked once somebody in the neighborhood learns the fire safety skill completely.
*Police are unlocked once somebody in the neighborhood tops the law enforcement career.

CLOTHING BONTIQUES
*Clothing Boutique must not exist until somebody in the neighborhood attains the silver/gold sewing talent badge.

PAINTING
*Each skill gain unlocks the painting with the corresponding environment score.

LITERATURE
*Bookshelves are locked until one of the sims from the neighborhood completes writing the very first novel.

VEHICULAR TRANSPORTATION
Those who have Bon Voyage or later expansion packs may not use the taxi service/rides. Ownable cars are also forbidden. To lift these restrictions, the vehicle must be invented via having any sim attain at least bronze talent badge of robotics and the same build one (with Restorable Junk Car) from the very first time in the history. This will also grant another opportunity to unlock purchaseable helicopters, but with another requirement that must meet: A sim with the silver talent badge of robotics must be present in the neighborhood.

Discovery of Fire (TS2:Seasons)
Kind of additional one, but not guaranteed to happen 100%. Once fire gets discovers (via lightning sets something on fire), sims during this time period age discover fire, in which opens up possibilities to create inventions of that are the element's -esque related objects (i.e. this is another requirement along with robotics mastery for unlocking just the stoves, grills along topping the culinary career, gives access for purchasing fireplaces, campfires, firejets, dinCo items, allows Sims to burn leaves and witches to cast inflammo spell.).

Anyone tried out this challenge?

I want to start a whole bunch of interesting challenges, and this is one of them. Haven't decided yet between a single sim start or random rolled families, prosperity style.

Anyway, the one rule I really don't like is the generations requirement. People rarely reach 10th generation with a single family in a legacy, and I don't think anyone ever played entire hood for 40 generations. You could make a rule similar to painting, like, each point in mechanical skill unlocks a comfort object with corresponding comfort score for that family... or something. Full fridge could be available when there's a grocery store and a gold robotics badge. Also, discovery of fire rule is kind of random. Is this some kind of "through history" challenge. If it is, then all other restrictions should be much more difficult to lift - you can't just get stuff for talent badges.

Perhaps I've missed it, but how and when do you add community lots?

Also, you could flesh out the starting conditions a bit more. What constitutes a simple shelter? What about beds and cribs? Ponds?

If I actually start this I might have more questions.

I feel refrigerator would belong below gold badge (as that includes artificial intelligence), perhaps it would be better for a silver one.

You just add community lots at any time as you want and as many as you want. Of course, you would have to progress to unlock that objects (a computer, a phone) that allow you to purchase and start running one, as you can't do it without any (unless you have custom content that is appropriate for the circumstance).

I think the lightbulb could be tied to mechanic skill point as you mention, which again is up to each player to determine when they would like the unlocking point to be present at, As for furniture goes, there doesn't seem to be or at least I can't think a method that would make perfect sense as a factor for unlocking the following seating and surface furniture. There isn't like sculpting or something of some sorts, so I would rather go by skipping that generation-unlocking-thing.

Basically, a simple shelter would be a room with doors and/or arches, a roof, wallpaper and floor tiles, fences with gates. Basically anything that's not listed under ARCHITECTUAL OBJECTS headline. Maybe I would apply the requirement of bronze badge for the garage door.

I also thinking that the telescope object should be locked until someone's maxs Logic skill, just so to put through sims for a taught challenging having to develop that critical thinking through daily newspaper crosswords before that object gets invented by the genius himself.