[Can I contribute with music?]

Just a question:

if I have a piece of music/ a track I have made myself, can I suggest this to the game? if so, where?

[Visual armor upgrades for Priests, and more...]

I imagine more Religion basically:

More: Visual armor upgrades for Priests: higher hats, different styles and masks (and maybe all other non-super-units that does not have this), maybe spesial abilities for priests, unique for their Civ. More obvius religion in the game. Perhaps unique pathways for a Civ to select, either a "warrior way" or a "religious way" of being. (The Egyptian priests are the coolest! (if color green))