Wow, thank you everybody--so, so much, I truly appreciate the comments and advice. Obviously, there's a lot to consider going forward, but here are a few notes on some of the questions people have raised:
- Buoyancy-wise, I feel like I've been doing fairly well. Certainly when I first started drysuit, I was playing with the dump valve a lot more. But on my last few dives, I feel like I've gotten to neutral fairly easily, with a minimum of adjustment necessary during the dive.
- 33 lbs of lead was definitely heavy...I started with that amount when I first began working with a drysuit, and I hadn't really reconsidered my weighting until this past weekend. Two guys I dove with are about my height, one quite a bit heavier than me, the other lighter, and both of them were doing 28 lbs with drysuits, so I dropped my trim weights to try it out. After that, I found I got to neutral much quicker.
- Kick-wise, I'm still working on mastering a frog kick, but I am doing a decent job of kicking less and using less movement overall. My hands are usually lightly locked in front.
- I'm definitely staying warm; I've got locking drysuit gloves, a heavy thermal Fusion undergarment, and a Whites drysuit hood. Most of my dives are Lake Michigan, so I'm usually in 44 degree water or thereabouts. The mine dive was at 58 degrees.
- I take deep breaths typically, not shallow ones; I do my best to be relaxed underwater, although sometimes I wonder if I'm just tricking myself and I'm more anxious than I realize. (I fully admit, some of the overhead environments in the mine got me nervous at points.)
I hadn't considered the tightness of straps, so I'll look into that too. And to be clear, none of my dive buddies have (at least vocally) been pissed about me running through air faster; it's just that I'd like more bottom time (obviously) and my breathing rate seemed SO high compared to others, I wanted to get some tips on techniques/approaches I can try out to start improving.
As for Bonne Terre...yeah, no personal tanks. They actually handed a lot of people 80CF tanks; I requested a 100 and got one out of luck more than anything else. And my doctor agreed with you all that the exercise I'm doing can only be helping me.