I'm glad your enjoying them. Unfortunately for the graphics I don't really have the skills to make something myself. You can check out my siege ballista mod if you want to see what graphics I make from scratch look like, and that was way more work than I'm interested in doing again. So I'm limited to existing game assets since I don't want to just steal someone else's graphics. (Tesla turret is just beacon assets combined with old crashed-ship assets on a turret base)
It's currently using the tank's turret which I think actually looks pretty appropriate tbh, but I could use the car's turret instead. The problem is that the car's turret has the ammo belt coming off of it which screams machine gun and that bothers me. I also don't like how similar it is to Vortik's; I'll think on it.
Not sure what you mean by 2x2 entity, is it not already a 2x2? Why would the size need to change?