I like lack of curration. Picking only the top titles would be good, if Steam would have at most 10% of DD market. But currently it's uncomfortably big in this area. And for indie devs being on Steam is often a matter of survival. Thus heavy curration would essentially undermine the whole point of being indie developer, with Valve becoming just another publisher devs have to suck up to and as a whole heavily damage the entire platform.
What Steam needs is better filtering and recomendation mechanism, so that people can sort through the releases better. At the very least Valve should steal Goodreads' mechanism of rating games and using this data to generate recomendation.
Well, we do know they're planning to offer user storefronts. If you find someone whose tastes are closely aligned with yours, you could subscribe to a curated list of games they recommend, which would presumably have some of the same options as the main store when it comes to new releases, top sellers, sorting by genre, etc.
I'm pretty sure they even floated the idea of paying people commission on games that are sold because of their recommendations, e.g. if Giant Bomb had a Steam mini-store and a random Quick Look or Endurance Run sparked a lot of interest in a game they had listed in it, they could get a few percent of each sale in Steam credit for something like that.