Looks like a pretty nice setup, but seems like that system is really going to be limited by the 2 batteries.
Have you looked at what you want to run and how many amp hrs you need? Running the AC is not really an option on 2 batteries. So, that leaves you the fridge, water heater, microwave, tv, and 110V outlets for stuff like a hairdryer, toaster, coffee pot.
Your diagram shows the entire electical panel being fed from the inverter. The other option would be a sub-panel powering only select circuits.
The easiest way to save on a solar setup is reduce your load. The fridge and water heater would run for a couple weeks or more on propane without a refill.
Just playing devil's advocate here, but 2800 watt inverter is a lot of power for a hybrid trailer. Depending on what you need to run, you might be able to go down to 1500-2000 watts.
And same thing on the pannels - 750 watts of panels is going to take up a lot of real estate (and be fairly heavy) for the roof of a 21ft trailer (or you have to carry them/set them up if they are portable).
And if you have them in series, you need to mount them in a way that avoids any shadows or you will loose a lot of output.
Food for thought, but if you downsize the system to power the basics, you could put the savings into a good generator. Even if you had to fire it up to run the microwave or coffee pot, it would still only run a short time each day. Or maybe even spring for a pair of 2000's that you can parallel. Run one as needed, and run both if you need AC.
Or if you stick with the current setup, a couple more batteries would really help maximize its potential.