Hi! I grow in my home and it is dry here, so maybe I can help a little. I have grown Phals for a long time. They generally have done well for me in coarse bark with some (about 1/4) sphagnum moss mixed in to add some moisture retention. I tend to underwater and they survive my neglect pretty well. When I water them, I often soak them for a time to be sure the bark and moss take up what they can. The seem to like my East windows very well, or under lights in the middle of a large and sunny room. I also tend to use glazed pots with holes in the sides as well as the bottom. The glazing keeps more moisture in, but they have good air exchange at the roots, vital for Phals.
I don't do so well with Oncidiums, too dry, too stagnant or something. My Cattleyas are in my South kitchen window in either med/coarse bark or S/H. I can keep track and keep them pretty well watered there, they are doing well.
I have a couple of Paphs with my Phals, long enough to rebloom one of them, but they are still in their original pot and bark medium (looks like medium bark). I put trays of gravel under them in hopes it will help them. They do need more water than the Phals.
That's a bit of my experience... I hope that helps you! I figure I'm about the same level as you are advanced beginner - years of experience, but not a wide variety of orchids and I've pretty well just done the same things and gave up on the plants that didn't make it.