Preflop:
1) Since you have position on him, that makes calling more favourable, as opposed to trying to reraise and make his decision easy. A lot of the time, he could just go allin, or just fold to your 4bet.
2) That could be true, but I think your info is still fairly limited. You should provide his 3bet stat too. Your sample size is really small too, with only 12 hands, so I'll assume his 3bet % is 0 for now. I don't think you can just jump to this conclusion too quickly.
What we do know about BB though, is that he is probably a very bad player. Most good players don't make such small reraises, simply because it achieves no real purpose.
3) If we can't get any value from worse hands, and we can't bluff out better hands, then I think reraising here serves no real purpose. We should consider our other options which is to either call or fold. Given that pot odds are really good, this is a clear call in my opinion.
Flop:
1) He is never folding a pair to your raise, not for one bet at least. To fold out his pairs, you need to put in multiple bets
2) Disagree with what you said, as mentioned
3) We do have showdown value. If you did put weaker broadways in his preflop range, all those hands miss this board. We beat KQ AJ KJ QJ on the flop, so we should probably just call the Flop.