I’m with you. I wanna play metal and not painted metal. I’ve stripped multiple cymbals. I‘m pretty sure the coatings are polyurethane so a paint stripper that included methylene chloride works well and is easy. But you will need to wear gloves.
Considering a single head ... essentially you have a fundamental pitch from the dead center and harmonics close to the edges. The first harmonic is mostly the only one audible, but there are a bunch more but very very weak. When you add a second head the two heads will resonate the same...
Well generally the bearing edges aren’t finished and there are holes for hardware, etc. If the finish is lacquer moisture can go right through it as it is more like fish scales than a continuous sheet.
Think about it like when you leave a wet glass on your table and get a white ring.
You have two issues. Sound reflection inside the room and sound transmission through the ceiling. Be aware they are mostly unrelated. Reflection in the room is relatively cheap and easy. Blocking sound from penetration the ceiling will be relatively expensive.