What would long term aspirations look like in Sims 4?

Yes I have thought about this a lot too. Although I haven't played any other Sims game, so I don't know how aspirations worked in them.

Among the ones we have in TS4 right now, only the parenting and getting rich aspirations are something that can take close to a life time, if one wishes to take their time with them.

I would like more general/spiritual/philosophical ones, like-
• Being a Good/Benevolent Sim (friendliness, gifts,charity work etc)
•Being Curious about life (knowledge, asking questions, research)
• Being a festive sim? idk (celebrates all festivals, uses calendar a lot, decorating, dressing up)

The first thing in my mind is the TS2 life goals, like having 10 babies. That would be quite something for my sims :D I think I would like something a bit different, but not sure what. Good question though since I do think we some longer term goals or dreams.

• Do you think those should be set by the game or by the player? I think it would be nice if the options were given based on traits and we could then pick one of the three. It would add some depth to traits as well.
  
• Could they be switched like aspirations? I'm not sure personally, but I would like them to be hard to achieve. Maybe you would first get you life goal when you become YA and then you could switch it on your adult birthday.
  
• What should the reward be? Personally I'm more interested in working towards the goal than the reward itself, I'd not want the reward to be overpowered.
  

How about kids who play with the doctor set develop the wish to become doctors when they grow up? Or if they gaze at the sky often enough they develop the wish to become astronauts? Or how about becoming a famous chef, where you first need to be able to cook excellent food, then own a five star restaurant and maybe write write 5 recipe books, or have a cooking show on TV, etc.

I think we need more of a constant goal, something that can't be fulfilled. Not a box to be checked off. This could be represented in ranked clubs instead.

Like a country club for the wealthy, you'd need to be worth like, 5 million to join. 1 million would be too little, sims get that without trying.
And whoever is the richest sim would enjoy the most privileges here, so being the richest would be a constant goal. And this could really be this decadent snobbish club that looks down on poor people. Wealth determines their whole pecking order.
The country club could come with a golf course, and being a member could give access to buying some special things and special services. It would be all about living a life of decadent luxury and hoarding money.

Another club could be for geeks, it would be a friendlier environment where geek credits count. Doing geeky stuff, winning video games, building a lightsaber, getting the highest rank in any star wars organisation, etc. would build up geek credits. Members can geek out with each other. Aliens would get geek credits just for being an alien.
Their club house could be sort of a geek paradise with gaming consoles, board games, lightsaber battles, robot building, cosplay, etc.
And members could have access to special geeky stuff too not found elsewhere.

And yet another could be all about healthy living and exercise, giving access to some interesting objects to improve related skills and health.

Could be a club exclusive to supernatural creatures too, save for aliens. It would be focused on the more mythical beings. Mages, vampires, mermaids, ghosts and hopefully they will still add more.

More clubs are possible, and all could determine what wishes pop up for sims, that could replace the stupid useless wishes that sims get like wanting to buy a bee box because it's spring regardless of their traits or aspirations.