Yeah I realised that a little later. The idea came from being able to give yourself analogue movement from your mouse cursor as well like in first person stuff, because that can be really useful in bullet-hell type stuff.
Instead it wasn't super userful for the whole bullet hell thing, especially when you have to make quick changes in aiming (which also changes what your WASD does) with enemies approaching fast without much wiggle room for failure.
TLDR: should have just used the gold standard of twinstick shooters and told people to use a controller to aim/move