Similar: Bundle subscription or freemium (e.g., include X credits at every month for the game store) MMO games from (at least) the major players under one account. Keep the individual game accounts active across all games that I've started, unless I explicitly choose to delete the specific game account. Allow access from multiple computers -- don't lock it in to only one "activated device". I'm only likely to be logged in to one game at a time. There could be a premium tier that would allow being logged into multiple (different) games at the same time from any of my computers.

You might be interested in GameTap (http://www.gametap.com/). Lowering the bar of entry meant that I tried out a bunch of games I otherwise would never have tried, but when I was using it there were constant problems. Downloads completed and installed successfully maybe one in three times. Mod support is iffy.