Lucky,
Glad you had a chance to explore it live. Hopefully you have a chance to listen in stereo - it makes a huge difference. Any single amp on a floor gags me...
I spend a great deal of time balancing the instruments for live play. Don't know why, but ALL keyboards' bass always drown out the rest of the instruments - I always tone those down first.
Strings: these should sound incredible! I do songs with strings that are absolutely top shelf.
Drums: I am totally happy with the drums, but that's me.
Pianos: again, if you play them in stereo, they should sound great. I love the acoustic pianos. The digitals are very good too.
Organs: The best going
Guitars: Glad you like them. They sure sound good in mixes and there are some great country styles. Add the pedal steel in the pads and wow!
Sax/Trumpet/Flute: Great
Horns: This is the one downfall IMO. That said, I do big band with patch harmony engaged it they come alive.
All I can say is everyone is different. I do believe we 'get used to' the small imperfections a board might have. I know I was disappointed in a FEW style choices I had to live with vs the 900 when I made the switch, but I got on and found ways to make them better - and now I'm happy (and I also forgot how the 900 sounded on those particular songs)
Of course, sounds and styles are the bread and butter. But if they are really up there and pretty darn good, remember the fantastic other features Korg offers. There are MANY inspiring and 'different' features this board will allow vs anything else on the market.
Good luck....