Remove the current stat system and put the system from a16.4 back in with tweaks, Darkness Falls a overhaul for 7dtd uses a modified A16.4 system and its perfect. A Overhaul called Afterlife even makes the stats action skills and has them tied to certain actions.
As for new stuff, Steel has been top tier since I started playing in alpha 10.2, Radiated zombies have been the top tier enemies for a long time. Game needs item tiers above steel and enemies above radiated, the game seriously lacks content. Why do you think they plan to extend the game in a22/1.0 by a factor of like 5-10? so it takes longer for new players to realize how little content the game actually has. Right now the game already scales way to slowly that it puts me to sleep, its going to be much worse in a22/1.0. As its the same content we have now, just dragged out to feel like a slog.
At least the game is easly modable, I prob have the majority of my hours in 7dtd in overhauls or heavily modded as the vanilla game is so lacking atm. I have 9473 Hours played on steam in 7dtd. Lots of mods out there to make the game fun and intersting again. Once you start modding the game basically no one ever touches vanilla again I notice. Gotta admit though, I deff got my moneys worth with 7dtd, more so than any other game, and I gotta thank the mod community for that.