Camping world has the nice polypropylene mats on sale right now... we currently have one 6 x 9 but ordered two of the smaller ones the other day over the internet.
They are really nice as they can be swept off easily with an inexpensive broom - wife bought broom at dollar store so it aint an expensive one
Glad your unit did well in the rain..
Suggestion - Wally World sells a spray made for slide outs - dry silicone so it don't attract dirt and dust.. We sprayed both the inner and the outer seals of each slide out and then actuated the slides twice to distribute the lubricant.
Also, I like to spray the extended portion of each of the hydraulic rams for the leveler legs just prior to retracting.. I think this will serve two purposes.. Cleans off the ram and lubricates the hydraulic seals as the rams are retracted back into the cylinder.
Another thing we added is a battery tender across the two batteries - one connection to one battery positive and one connection to the other battery negative terminals. When we are back home I plug in the battery tender and it keeps both batteries maintained.