Got 2 more missions to do on GTAV then the story is over. Was looking at my 100% log and seem to still have 6 Strangers & Freaks missions and lots of side quests to do despite not having anything showing up on my map as unfinished? Also seem to have never, EVER found 1 single UFO part yet. Oh well.
Think I'll buy Arkham City today and just dip in and out of GTAV once I've done the final mission; seems like a good open world to have the odd cruise around...