Yah i was thinking about that, given his drawback i see him as quite hot tempered. I can switch out his racial things so that he appears very human, i think he would lose his +1 nat armor as the trade off.In my opinion. I would put your stats at 17 / 14 / 12 / 12 / 17 / 10
if you insist on keeping his CHA at 5 I will expect you or whomever is going to be controlling Gunther to RP him properly. This campaign isn't just hack & slash and interactions with other people is expected (unless you plan on keeping him locked away whenever you aren't fighting and that will present its own problems)
Wisdom is both the trapfinding and tracking stat (perception and survival)Is there a reason you pumped up his wisdom specifically? why not drop wisdom and str back down to 18 and put some points into CON and INT