Coir
I put everything into a coir, diatomite, charcoal mix. It's called Aussie Gold. Expensive stuff, but real easy to use and I reuse it by baking it in the oven at 350 for 45 minutes.
My phals love it, as does my zygopetulams. Amazingly, as a test, I also potted two vanda's into it in net pots and they've done really well with roots growing everywhere...so much so that I'm thinking of potting up my remaining 25 vandas. I've got 12 catts growing in it and they seemingly like it (again, net pots). My phrags are all in it and I've recently gone to letting them sit in about 1/4 inch of water and letting the water wick up. They are all performing well, too.
I've had great and not so great success with paphs. The majority do really well. Some want their roots a little drier. New roots growing into it do extremely well...it's usually when you transplant something from bark that you run into problems. On troublesome paphs, I put them into net pots to keep dry the media a little faster.
The majority of my paphs have developed very strong roots. The key, that I've learned, is to make sure you underpot since the media tends to be a little wetter, and also to use net pots on the sensitive plants.
If you make your own mix using coir, make sure you add perlite or something else to provide some aeration to the roots. The reason diatomite works so well is that as coir gets really wet, the diatomite pulls the moisture from the coir and, as the coir dries out, releases it back into the coir keeping everything at a relative uniform wetness. I notice that when the top layer is dry, almost the entire pot is dry (it's that uniform). Obviously, if you let the plants stand in water, the media will stay very wet. I learned that lesson by using trays without holes and wondering my some of my paph roots were badly rotting. A few holes in the tray fixed that problem and all the plants bounced back with new root growth.
Of course, I'm also in Tucson, so I'm fighting to keep 60-70% humidity in the greenhouse. I also profess to wanting/needing some type of media that doesn't require a daily watering. In winter, it's like once a week. In the summer, it's every other day, but I can go a weekend if needed without a problem.
With that said, I'm also going to experiment with lava rock and CHC, but I currently have 200+ plants in the coir mix.