tldr: I believe game play screenshots would make the site more usable.
Currently when I use the site the first two things I do are check the category buttons to see if they interest me and if they do, I scroll down to check the steam store so I can see photos of game play. This is a pretty basic usability problem in my opinion and I think screenshots would greatly benefit the main page somewhere.
I believe the trailers section is not enough because I don’t enjoy video game trailers they never really get me excited for a game. The twitch section also is not suitable due to the load time (about 4s for me with 100 down) and for some games story elements I don’t want spoiled. It is useful when I want to see some more game play in action to decide if i want the game.