(Just so you know — the optimization I mentioned earlier kicks in when you have 40 or more characters, which is why that number seemed like the "point of no return" for the crash.
On my machine (which is probably a bit more powerful), the issue didn’t show up until around 100 characters, when the second wave of optimization started.
(0 -> Unoptimized
40+ -> Optimized lv1
100+ -> Full Optimization
It doesn't do the full optimization right from the start because it's like sending a full armored tank against... a brick. It's too much, when a simple hammer is enough.))