Game Clean up

which list specifically do you mean? if you mean the achievement list for your gamertag, you cannot remove those. if you mean installed games from the My Games & Apps, then you can press the Menu (Start) button, and go to Manage Game which will allow you
to uninstall them and free up space on your hard drive. if you mean games showing under Ready To Install, then you can press Menu and then choose Hide to have them not show up there anymore.

I'm finding Xbox store harder to navigate.

All game editions, deluxe and addons etc.. should be put under one title.

Low quality games should be restricted to a separate section.

I can't really agree with you that "low quality" games should be restricted to a separate section. Who exactly determines what games are qualified to be considered worthy of being promoted in a 'High Quality" games section? Just because of a low budget for
a title. Does not mean that the game will automatically be any better (or worse) than the other.

The store is definitely improving in a lot of aspects, but I can agree that a cleaning up of the store is/was needed.

Submit you ideas at Xbox Ideas

you can submit your ideas here:

https://xboxideas.uservoice.com/

Let's say I create a poor quality game with zero effort that get's put next to a game that took 5 years and a lot of effort to develop. That should not get equal representation in the store, arguably it shouldn't even be in the store.