Hummm, sounds like you have been doing a little homework concerning the rising fuel prices and your decision to buy a used class A.
Only thing I would be concerned about is the 2004 Odyssey was known to have somewhat of a weak transmission. You will definitely need to install a tow kit which consists of a trans and power steering cooler. Otherwise your plan to go smaller sounds great.
Have fun and Good Luck!
'98 Gulf Stream Sunsport 325, 7.5L Banks Power Pack, Koni FSD's, Air Bags, ReadyBrute Elite,
2000 Honda Accord