Maybe have a single page where you could actually see what's going on in all of the dozen (or more) important repos... I'm thinking right now about @wxop's improved ToH interface, and dreaming of something that could aggregate the various github mirrors, select "Commits", "PRs" or "Issues", then select by date range ("most recent 7 days", "last comment over 1 month ago"), plus all the other search/select/sort bells and whistles.
If you could filter down to a list fitting your personal competence or interests, then you're more likely to do a review (I know a lot of stuff just goes completely under my radar until someone @s me or I stumble across it here on the forums).