check out tanyastreeter.com under workout schedules. It should give you some ideas.
I try to get 3 hours a day doing something. Two hours lifting weights and one hour of carbo. I watch what I eat. Got to get into the pranayama stuff like you do though. I'm thinking about getting a bike because my knees hurt much from running.
I hold my breath a lot. When I'm driving, taking the elevator, walking etc. I often do a sudden breath hold without taking a big breath so I get more familar with the pain.
They say if you spend much time with your heartrate above 85% it builds up your lactic acid tolerance. (or something to do with lactic acid) So I try to do at least one hour of that. When I work out with weights I have a heart beat monitor and I try not to let my heartbeat rate drop below 60%.
I've been hearing much talk about how "packing" your lung can really make a diffrence on your dive. Look up lung packing in the forums and you should be able to find a link that will take you to a detailed direction on lung packing. It's at the end of some equalization page. If you can't find it let me know, I'll pm you.
If I had to stress one thing it would be carbo, carbo, and carbo. The more efficient your heart pumps more your body will work underwater. But don't forget to get your legs buffed up eighter.
Good luck!
P.S. Metrix protein shakes are great!