Are you looking to do a keyboard or module?
Looks like you have enough Yamaha sounds, I think Roland is closer to a Yamaha sound than Korg, I found that the Roland has great styles and great sounds except for some that come across a little thin hidden in allot of fxs, ( just an opinion ) Korg is a more raw sounding machine, more of a love/hate.
Give me a call or email and we can discuss more if you like