Other than the surge protector rating (see below) no obvious flaws, other than you may have to practice power management. You probably can't run the water heater, A/C heat strip, and microwave all at the same time.
I am assuming that you are wiring for a 30-amp shoreline if you are using a 30-amp protector. Remember that "30-amp" RV shorelines are 120 volts, so the capacity is only 3600 watts. The 30-amp surge protector will be undersized if you use it with your 6500 watt genny, unless you are planning not to stress the genny, or have 240 volts from the genny through a 240-volt surge protector (7200 watts).
"50-amp" RV shorelines are 120/240 volts, so they actually provide two 50-amp 120-volt feeds, for a total of 12,000 watts. Just remember your limitations, add up your loads whether on shoreline or generator, and plan accordingly.
If it was me, I would make the water heater propane instead of electric. If you were planning to be at campsites and not racetracks, the electric might be included in the price, while propane refills always costs you extra. RV water heaters usually can use either. Plus, there is the complication of installing an additional system of plumbing, etc. For a race bus, load management may be the simpler choice.