I think part of the reason you may not be getting any responses is that people like to see your own creativity when it comes to customs. If every custom was a group decision, it would take forever
(I hope you take that with the humor it was intended).
Anyway, for what its worth, here's my 2 cents on your questions. I don't think there is anything wrong with the standard saber colors. in KOTOR they still used traditional color blades. However, if you want to change colors, I wouldn't use silver (too much like a regular sword). Perhaps you can get some sort of marbleing with a green and a gold or bronze?
Han will always been noticeable but if you "hide" him with other custom features, I don't think people will just assume its Han. Change his hair color, try something like that.
I'm not sure about the inner species breeding but everyone likes a sexy Twi'lek. I say go for it.