Something in the 5-15 mile range. My go to is the 10 mile but that's bc a town I lived in did a weekly one and it's 20-30 minutes for most so I can get a warm up and cool down in about an hour or less depending.
I want it to be ITT bc there are plenty of drafting events and I trust the ST crowd a little more. Gonna have to do that weight thing in another thread. Also would be fun to compare a similar course outside in the spring.
Main limiter would be whether people were riding in aero position or not I guess. Could lead to some good data and discussion, possibly.
Also might be easier to do multiple times as the race u mentioned is basically east coast only.