Thanks for your compliments, everyone!
To answer your questions, I'm unsure what clones any of these are, unfortunately. I did try to identify some but it seems like Miltoniopsis hybrids are as difficult as phals in this regard!
I do still allow them to dry out almost completely between waterings, but because of the nature of the medium the drying process takes a lot longer. At a guess, I'd say I water about every 2 weeks. I did try to ensure that there were plenty of air gaps remaining between the individual cubes of wool, without packing the medium down too much - I suspect it would be too smotheringly damp if I had done so.
I hadn't actually considered health risks of rockwool - perhaps I should have done! I haven't found that it is released into the atmosphere much during repotting, though, unlike the dusty perlite which I can be a little leery of.
Update: Milt #3 has opened its blooms! Only 3 on this spike, but I noticed a sneaky second spike started from another bulb too