I can't address all of your ideas, but here's a few thoughts.
I like the backup camera idea. Let's face it, the rear-view mirror doesn't help much since it seems to be mounted at the wrong height. I can understand why it is mounted where it is, otherwise it would impact front vision too much, but it's really too high to get a good view out the back. My side mirrors get bumped by tree branches so they aren't always effective either.
Mine came with the bed liner already sprayed. I like it. My previous TC did not have the liner and I like the liner better. Not sure about putting in the foot well areas. Mine gets so full of snow, mud, etc. Not sure how it would be to clean it out with the bedliner sprayed in?
Like any receiver hitch winch setup, you'll want to make sure you are pulling fairly straight. Side pulls are not good on any piece of equipment.
One modification I've considered making is installing some Anderson-type battery cables. If you ever have a dead battery, you have to take off the fuel filler panel cover to access the battery. The Anderson quick connect flat cables would be really handy. (Or, I could always make sure the battery never goes dead! LOL)
I'm also thinking about an LED light bar, possibly mounted under the brow. Not sure how I would fit it in though. I mow under and around lots of trees with the TC so the light bar would need to be protected.