I know. Mine is very patient but they all have their limits. I fiddled with it too but yesterday I had to take it off twice. She gets such a surprised , what happened look on her face when I take the bit out though:') Overall , I'm happy with it.
I know what you mean about the reins being heavy. My older nylon trail bridles don't have that rubbery coating on them and they are lighter I think. I also don't like the fact that the snaps on the ends of the reins are attached with a buckle. That adds extra weight too. I'm thinking of removing them and having the snaps sewn on. It's not the best solution, but it's better than what's there.
The reins on my old bridles are doubled, stitched nylon their entire length and they have a loop at the ends that you stick throuth the eyes of the snaps and run the reins back through, so if one of your snaps ever breaks, you just un-loop it and put a new one on without having to cut stitches then re-sew. The old guy who made them really seemed to think of the little details when he was making them. It's hard to find that kind of craftsmanship anymore.