I simply had trouble wrapping my head around which control go in which direction.  Maybe an idea would be to simply map the controls depending on the actual direction on the screen? (For instance, pressing S and D would make you go down-right and simply S would make you go straight down.) It simply is an idea though, maybe not what you envision for your game. I personally think it would be more intuitive.

Edit: I somehow missed  the part of your response about the controls similar to top-down. I'm guessing this is what I'm talking about. Guess I don't know what the right solution is then. It may actually be fine as is, but is certainly takes some time to get used to.

You can get used to controls pretty quickly working on your own game, I know something about it, most criticism on my game this jam is about unintuitive controls x)