1. Unlimited fire buttons, or at least 4.

2. A "digital" d-pad alternative. I'm not a huge fan of the touch the center and drag to the side control pad. It works for some games, but I find that I always end up dragging my finger too far off of it. Unlimited fire buttons could solve this as well since you could just use those as your left and right controls (assuming you're not using a built in movement)

3. And I said this before in another post, but I'm still not finding a good way to make my own 'press and hold buttons'. It loses track of your finger position in scrolling games.