Honestly, I did start several chars, among them a 10 con tank supposed to wear metal later. I haven't picked thick skull as of yet; As far as I understood, con already reduces your chance to be stunned, and I expect to have enough resistance to survive 2 turns of stun per combat.
I actually wonder if Doctor is still a good feat, I kind of expect to never drop below the threshold where I can't use normal bandages; Maybe fast metabolism would have been preferable to go with a regenerative vest.
I can agree that steadfast aim is a bit questionable, not because 2 stat requirements are irresponsible, but because strength and dex is rarely ever taken together, so you'd spend several statpoints more or less only for that feat.