If I could guess what Seth will be like from what I see now, at 5 months, I'd say he'll be sensitive, but I hope not in a timid, painful way. I would hope he'll be sensitive to other people and the things going on around him.
He's not a real complainer but can get really loud quiet suddenly whether he's happy or mad.
He has a temper on particular things. He'll be strong in the legs as he is now, kicking the crib mattress hard, when he's happy but especially when he's mad.
He won't be vain. When I show him his face in the mirror, he smiles big and feels compelled to wiggle and look away, similar to how he plays shy with other people when they make eye contact. He will like to laugh, amuse and be amused.