I’ve been playing the new Solium Infernum with a friend - the first playthrough I did not particularly enjoy (partially my fault for not playing the tutorial first) but once I learned the mechanics my second game was more fun. The UI is not very smooth to use and there are some mechanics I don’t like, but overall pretty good.
I also picked up Mindustry again last night - it’s an open source Factorio + Tower Defense + RTS that is rather addicting… The new campaign they added a couple years ago is better than the original too.