I've been using for a little while now, and I'd say the only issue I have is not being able to tap on players while they are in the joystick quadrant, so to speak. It'd be nice if the joystick only reappeared if one started dragging their finger in the joystick's area of the screen.

Also, the joystick disappearing off the screen when stationary seems to be one of its key features (thus being able to see more of your surroundings). I'm not so sure why people are asking that it stay visible.