Should this be a webgl package or is an executable okay? 

I'm struggling timeline wise as i joined late and wasted time trying to use off the shelf character controllers that just didn't work correctly for a quadroped main character so im having to roll my own controller. I'm assuming it will be okay if I drop mouse and keyboard support and focus on gamepad?

Hello. Yes, there’s no rule in the guidelines stating that you must use only a keyboard and mouse. You can create your game however you like. I think you should just specify that the game requires a gamepad.