If you need help deciding, let me know. For example:

The 35 mile option = more of a fun ride for hybrids.
The 63 mile option = fairly large start. You have one river crossing & a short but straight-up hill. Other than that - a nice ride.
The ~80 mile option = typically only a few hundred people start. You may catch up with the 63 mile-ers around the river crossing.
The big one - huge mass start. Two river crossings.

Of course you know that river crossing doesn't equal water. Just a big dusty wash, 99% of the time.