Yeah the no free spell hand rule is going a bit far. That and restrictions around drawing weapons are probably the most hand-waved rules in 5E. No one wants to manage that crap. It’s not OP just to let that go. Dungeon Dudes did a good video about it recently, worth a watch.
It is worth noting though, that in Solasta you can manually tweak that specific rule off without changing anything else, if you want. You can go through the vast majority of rules that are commonly hand-waved or adjusted at player tables, and set them up for the way that you feel they should work.
