Ok, so I don’t think I explained my thoughts on crushing well. It’s not, in the real world, bludgeoning damage. I can see why they chose to not have a crushing damage type and just use bludgeoning though, as anything susceptible to one would be susceptible to the other.
Ugh, bringing AC into it is a mess. But I think your approach results in the tennis ball lasting an average of 20 hits in a game between two strong opponents. And less time the better they are at playing tennis?
I think you’ve moved the goal post, but perhaps in an interesting direction. If the goal is to simplfy the damage types, what do you lose by replacing force attacks with other types? I think you lose an impact type of damage like damage to creatures you can’t hit with a hammer. Magic missle goes from best to worst spell.