Weirdness....
 

After a long marathon session (where I found out that yes, you can give cell phones as gifts to the hobby people and homeless prospective tenants, then call them), my game suddenly started crashing on whenever it loaded a lot, including the one used for "family group" in CAS! This was not restricted to one neighborhood.

With great difficulty, I managed to salvage almost everything, including the first family I tried to load and evicted to try to fix the problem. The only things they seem to have lost, as well as their aspiration rewards, was the novels they'd written. So this is my current theory for what caused the crashes.

Has anyone else tried writing novels with the new FreeTime interface?

Well, I've disproved this theory...

My new theory is that it was some bizarre confluence of old Sims, missing custom content, and many "iffy" actions in one play session. Just hope the other houses don't have the same problem!