Regarding floor layouts and front storage.
The Rockwood A122BH / Flagstaff T12BH has an exposed storage rack on the front and is the primary reason we purchased that model (along with the bed). You could mount a pickup-truck toolbox in that area to have enclosed weather-proof storage. You could also build a weather-sealed 12 to 18 inch tall plywood box that fit exactly into that shape. Put on gull-wing doors and then the top of that storage box becomes the floor of any additional storage you might want to put on there. I'm planning to do something akin to this (probably the latter idea),
There is also the "Toy Hauler" model (Rockwood A127TH / Flagstaff T12SDTH). It has a much larger front deck and you easily could add weatherproof storage to the front and still have plenty of space to spare. It doesn't have the rear bed, however. What it does have is a convertible couch with two lengthwise cushions that convert to the same sized bed. You could simply leave it set up as a bed all the time and add a 2-4 inch foam topper (or even a new mattress entirely) for comfort, and effectively have the same layout and more storage than the *BH. Watch your tongue weight, though.
If my tow vehicle could have handled it, we would have gotten the Toy Hauler model just for flexibility and just left the couch in bed mode with probably a new mattress.
BTW, the stock bed isn't terribly comfortable. After two outings we're debating adding a foam topper, or just replacing the mattress entirely (definitely one of those two). The heated feature isn't something we're that concerned about and if we ended up missing it we can accomplish the same with a headed mattress pad or electric blanket. It's AC powered anyways, so only available with shore power unless you have an inverter.
2012 Lincoln MKX
2013 Rockwood A122BH A-Frame