While cosmetics and titles have been great, we're slowly running out of things to buy. 3 people have already bought everything in the shop, and more are approaching. I know Buckethead is already working on more cosmetics, and I think that's great, especially if they start to make it regular with each new update, but I feel like we could also use Gear coins for more things.
My idea was to have expensive unlockables in the gym, such as a large training area, or even just silly things like trophies and graffiti. I think this would give a lot of personality to the gym, and would be a cool thing to work towards.