Yeah, I agree that controlling units like in a classic RTS could create that “bad RTS” feeling in this game.
But with the current structure, the castle in the center still needs some help from mobile units, not only fixed guards or spawned units. Sometimes the army just can’t get there in time, like I mentioned before. Even if they arrive before the castle falls, if all your farms are gone, the rest of the run basically becomes impossible anyway.
So instead of selecting and controlling units like an RTS, maybe units spawned from a banner/guard post could become loyal to that post, almost like a small patrol group attached to it. That might solve the problem without turning the game into direct unit management.
You could maybe even add a simple play/stop button on the guard post. When it is on “play”, the units behave freely, like this system doesn’t exist. When it is on “stop”, they return to the area around that post and defend it.
I think this would feel less like a tiring RTS mechanic, and more like adding value to the current idle defense + hero control style.
And yeah, I did try a few combinations and playstyles that made sense to me. I’ve actually had some ideas for making original games in this kind of genre too, because I think it’s difficult to design well, but also really fun when it works. Your game feels really nice too.
Good luck with the game, man :)