I'm primarily a piano player.
My main board is a Y-P250 (similar to as P-300 / CP-300), which gets me all the actoustic and electric piano sounds that I need, pus some organs / horns / synths. I've got some preset splits (e.g., clav left, org right) so that I can get by with just this one board, if need be. Replaced a P-70.
I'm currently using a Roland VK-7 as my B. I had a Hammond XK-2 before. Sold it when I got the P-250, thinking that I'd go to one board, but I really like the flexibilty of B style controls for color and animation, and grabbing a handful of keys from the second board always feels cool.
My third board is a Y S-90. Lets me set up some synth sounds or an alternate piano / clav without having to futz controls on the 250 during a live performance. This replaced an S-80 (again, thought I'd get down to one board with the P-250). Similar board, better interface / control set, it's just missing the "Kickwheel" patch, so no Karn Evil 9 on this one.
I pump them all through a Roland KC 550 (or two).
Used to have a Motion sound KBR for the Hammond. As good as some of the digital sims are (and Hammond is the best) you can't beat mechanical horns moving air. Again, sold it when I tried to trim down to one board.
Then there's the C-2 in my living room. Don't get to play it much these days.