Thank you saltpastillen, I will give it a go and see if it's satisfactory. And Serenity S., My problem is quite severe, I spent more then half my sims 3 time waiting for the game to unstuck.
It could be you have too many items in use, (large house with a lot of items or people), or have edited the town so there are too many people or buildings. I remodeled SV at one point and made it just the way I wanted it with lovely houses full of things and more people and all the different kinds of buildings with all the different kinds of jobs. It was unplayable then because of lag. The reason we get the lag when we add too many people, buildings or things is the game has built in limitations for both people and buildings, and each item we add, no matter how simply, means the game has to identify and render it. Even if you clump things together or overlap them still each item is counted by the game and it slows everything down. I'm not saying it very clearly but it is something you learn when you start using CAW.
As for schools not working well in the future, I think it depends on where you put the schools and which ones you choose. I put a school, a grocery store, arboretum and vault of antiquity, (all of them are rabbit holes), on one lot in the area where all those greyed out houses are. I bulldozed one of the empty houses to obtain the lot and used the school and grocery building from Lunar Lakes so everything would fit. I had 15 children attending the school from grammar school to high school and from both Oasis Landing and the little greyed out village area. This was in the Utopian future.
The grocery functioned just like a grocery would. I could buy my lottery tickets there and not have to go back to the normal world. I checked the city hall records, then bought a ticket and voila, won a million without every leaving the future.
The only problem with owning a house and living in the future as far as I can see is it messes up your time traveler opportunities. They wind up in a loop and never complete. I've not tried getting a job at the grocery store or school and haven't tried any other buildings that could have jobs.