To the first, it's hard to say w/o knowing how big/deep...I know cocoa butter, shea butter and vitamin E can be rubbed on some scars to lessen them but the degree of help depends on the nature of the scar...if it's a real problem, one solution is possibly asking a dr. or health care expert...plastic surgeon...NO, don't think u have to do major surgery! I'm thinking a small injection could smooth it out enough that regular cover-up sticks or concealers/foundations would then work.
To the second, the best contrast for a blue eye is brown...it really makes blue eyes pop. If you wear clothes and shadows in blue that will also make them seem more blue...need more? This was basic

Just ask, I'll be happy to give u more.
XoXo
Mychele