Here is the floor info that I did on mine this past year. So far it has held up good.
http://www.striped-bass.com/Stripert...ito-fleet.html
some more floor info from back a few years. Installation crap.
http://www.striped-bass.com/Stripert...oat-floor.html
Not sure why you are putting ridgid insulation under floor. What are you looking to do that for?
no carpet as like U said it holds moisture. Maybe build a platform from bow tip over the front seat. I luv to stand up on seats so that would help a lot. I may do that to mine some day, been saying that for 20 years. It would be great if you could lose both middle seats but like I said before it may be a structural thing. I have no middle seats, mine is a 14'er though, and it is great to be able to move front and back, esp. if you got an Albie on the line. PIA jumping over seats. I like it open. I made floor in 2 parts so i can take back part out easy. Tons of crap goes under floor, like eels, and they don't come out so you need to access them. I also ended floor just under back bench so I can slid it out easy to get dead rotting eels out. There is no floor behind rear bench. Really no need. Just put gas can on bare alum. Plus that is where water will pool so it tends to rot out the floor back there on the end grain. Let me know how you make out on the painting as I really need to paint my boat inside and out someday. Been thinking of just paying someone, auto body place, to do it. I don't really have anywhere to do it during the winter. It needs it bad. Looks like crap now. Good luck. Best fishing equipment you will ever buy.