A most excellent game!
My only gripes are with the pacing (the first 3-5 points of renown take longer to collect than the next 20+) and replayability (most side quests, encounters, etc. are shared between the three main quests).
In my humble opinion, it would be cool if, after finishing one of the main quests, you could continue to another, using the same character and world. That way, you can experience all the main quests, without having to grind up to a high enough level three times on largely the same side quests, encounters, etc.
I'm looking forward to playing 4x4 Galaxy.