Hi Vanessa. That's the beauty of raising 'chids (both kinds) the more experience you have the less you realize you know about the process.
As for humidity, it depends on the type. Cats in general like humidity but really will tolerate and thrive in a variety of conditions. Your windowsill sounds fine as long as the leaves are light to medium green. If they get brown spots you may be sunburning them (don't think east window should do that though.) You have read correctly that trays don't serve very well to raise humidity however they serve a very different purpose: they catch the drip from watering. I would keep them. The humidity where I grow everything from Encyclia to Cats to Brassias to Paphs to Phals and some minis of various types has very large photographer's darkroom trays lining the bottom of the windowbox. They have gravel in them and "egg crate" material over them as a grate for pots to sit on. My humidity runs from high 30% range in winter to 60-70% summer. All the 'chids, except for the Miltonia, are doing well and reblooming.
I think you should keep up with what you are doing and just watch for signs of stress before making major changes.
Hope this helps.