Based on your pictures of your three-shot groups, I would bet that if you shot each of those loads as ten-shot groups they would all be pretty much identical. I'd say pick one that has the velocity you want and run with it. Or, pick the 45 grain load to make your powder last longer, if you're hurting for powder. That's a round about way of saying "nice groups" and, "pick one". Personally, in my opinion, based on how good your groups are in the photo, seating depth is probably not going to matter much. It looks like you are there. Like I said, that's just my opinion.
This was along what I was thinking. I wouldn't worry about the seating depth.
Buy/borrow a chrono and see what you can't see without it. Shoot the same loads in groups of 3, and compare the second groups to the original, consider the new velocity data, and go from there.
All that said, I'm a generic load fan. If it's at MOA or under consistently, and it will do it from different rifles, I'll take that load over two different .5 MOA loads for two different rifles.
