Speaking of titles that are not yet available, it is good that you disabled the ability to create reviews for games which haven't yet been released here, but which have a game page (pre-orders and such); now you should follow through and disable the ability to rate such games too, and probably wipe any existing ratings for such as-yet-unreleased games. It makes no goddamn sense for, say, The Witcher III to have any rating, let alone five stars (as much as CDP might like the advance enthusiasm :) ).
Also, the ability to not only edit reviews, but to alter (or delete) ratings for games, and to "un-vote for" things voted for in the community wishlist sections, would be welcomed by many.
I would hope it's something you're working on -- or at least thinking about -- for Galaxy, but having a page in each user's profile where she has the ability to see every wish she's voted for (and the ability to "un-vote" right there), the rating for every game she's rated (and the ability to re-rate or "un-rate" it right there), and which games she has reviewed -- and when -- would be a great boon to a lot of GOGnards™.