Most of this stems from my engine not being made for turn based stuff.
So I have to
a) invented all the tools myself (which is fragile)
b) work against my engine.
Which is why choice of engine is super important and knowing what your engine was made for.
Like GMS2 is made mostly with 2D platformers and other action games in mind.
Of course you can do anything with it, but it gets complicated and you have to work against it.
And I mean, you can do 3D games in GMS2, sure. Nobody will prevent you from that.
But honestly, other engines (like unity) are made for such purposes and provide more guidance and tolls.
Other way around, if you want tile based 2D action games, unity is really not your friend.
Sure there are addons to allow it, but GMS2 has more tolls right from the start and is literally built with that in mind.