I mean, there’s enough game there that people routinely run “Auto resolve only” multiplayer games, so clearly there’s a decent number of people who think it’s worth doing.

Alternatively, if you want to keep the tactical battle element but find the “real time” aspect hard to manage, I’ll point out that you can give orders while paused. So you can effectively make it into a turn based game. Total War combat is pretty slow already, compared to stuff like StarCraft, and there are plenty of tools for building multistep orders and so on.