Hi! For the tire sizes I'm hoping there's someone out there making race tires in sizes like 4.00-18 / 3.25-19, but from asking around in the meantime it seems like tire availability is going to dictate wheel size, not the other way around.
The record I have my eye on is APS-Omega, or if I don't get a faring together in time, A-Omega. I came away from the salt this time with M-Omega and MPS-Omega, but I was limited by, you guessed it, tire rating.