Tim,
You're not losing your mind. You're like a lot of us here ..... a kid in a candy store. There are so many cool features available that it's impossible to assemble them all into one unit. Never happen.
My advise is to play the one you like till you don't like it anymore. If money is not an issue....just sit on the kn as an alternative. Old ties and shoes come back into style ... you may find yourself yearning for a kn -fix later on.

As a full timer, I can't keep too many old dogs in the yard. I need to stay abreast of the newest tools so I can keep my game sharp. It's not a love affair with me ..... it's a case of survival.
I'd love to have just one unit for stage and a duplicate in the studio, but till I get that exact match ...... I experiment.

Experimenting is healthy. It's good...and if you find that the kn isn't keeping up with your expectations ... then play the Yamaha, but don't question your sanity or business sense. These are just tools...nothing more. They are made to SERVE our needs. Play what you like. Life's too short of be unhappy while playing music. Music should MAKE you happy, right?

Go with your heart (and ears) on this matter .... you'll be fine. The companies have no loyalty to the players. Why should we feel bad about changing preferences? They make what we buy. Period. Happiness is derived from the playing we do after the sale.