I like the use of colours on the S3.
I think it would make sense to use the same colors (EQ, DYN, Insert) for the Channel Encoder Assign keys.
Very important in my opinion is a flashing or red LED when you have the faders in "Flip" mode.
On the right Fn Keys it would be nice to have different colors as well. But I hope they will become custom EuCon keys with custom colour anyway...