Possible solution for not being able to see your entire picture because you're zoomed in all the time. you can have an extra window that shows the file you're working on and the edits you're making to it. it doesn't have to be tiled but i did so for convenience
clip studio: window -> canvas -> new window
sai: view -> new
I'm not sure if photoshop has it because I haven't fiddled with it quite enough
Also more of an obvious thing: highlighting limbs/etc as if they're a 3d form. so putting the highlight on the bicep on the 'curve' of the bicep vs the edge of it. this like blew my mind when my teacher told us about it :y