Crikey, this is difficult. I think with a game where failure is expected to happen this often, it might be nice if things were to move a little faster? That might make it feel less frustrating :-) But that's kinda the point of it, of course! Good work on capturing my attention, certainly.
I think this doesn't quite adhere to the 84x48 pixel restriction? When it's zoomed up, lines don't seem to match that grid and seem a bit thinner than they should be, perhaps. It may be fine at 84x48, of course.