Hmm... I didn't realize the all the non-armor +AC things require attunement. If your GM is generous with stuff (and one of ours is), I can see that becoming a bit of an issue. But still an extra +1 on your AC seems like such a huge issue to you guys? So your AC goes from 18 to 19, most decently challenging enemies are still going to hit better than half of the time. I suppose it makes the mooks that do have to roll high to hit seem even less dangerous. But is that really a major concern?
I can see why you think the hand crossbow is a better weapon if-and-only-if the PC take those 2 feats. But those two feats made it powerful. A +1 to hit and damage just doesn't seem like it really adds all that much. The PC was probably already hitting most of the time. Now one out of every 10-15 shots he will hit when he would have missed. And he will do 1 more point of damage when he does hit (2 on a crit).