I'm at 35% on SoM. Only on 7/20 for the story missions, but a lot of the other stuff is closer to 50%. Halfway through the next-to-last tier both for abilities and weapon upgrades. Combat has become a lot better and a lot worse at the same time; moves and abilities are now varied enough that I can dominate an entire army of orcs pretty much endlessly, but the army just goes on and on and more because orcs keep arriving as I kill them.
Did quite a few of the randomly generated missions (the orange ones) trying to get decent runes and ability upgrades, but I think I'll scale back on those and just focus on the story, weapon quests, and collectibles.
BTW the survivor and hunter missions aren't very fun at all. The survivor ones because the map plants show up on is so tiny (maybe there's a way to zoom out--I haven't checked) and hunter ones for the same reason. Right now I'm supposed to kill rats but it seems like I never see the damn things while I'm wandering around.