2 - Privacy by default.
3 - Transaction fees should be a percentage IMO.
These two are in direct conflict with each other. A privacy protecting coin reveals no information about transaction amounts, and therefore cannot make fees dependent on them.
3 is really a bad idea...
I'm pretty sure if Monero has a way to obscure transactions without anyone know who is sending transactions or how much they are, they can obscure the fees too. You may know someone on the network has just transferred a transaction worth $x, but you wont know who at all.
You didn't elaborate on why you think 3 is really bad idea, and noone as yet has given me what I think is a reason that would make percentage based transaction fees an insurmountable problem.