We are in the process of replacing ALL carpet in our coach. We are using floating FLOR carpet tile squares throughout. It's thickness is about the same of the luxury vinyl planks we looked at and it has a durable look and feel to it. As far as interfering with our slide, ours has enough clearance throughout the travel in and out that it does not touch the main floor, so there shouldn't be any problem as long as we don't install it over the rollers.
As far as the surface under the Captain's chairs having to be carpet, I cannot see any reason except to cover up the bolt holes and the imperfections that the original manufacturer covered up with carpet. In the process of replacing our carpet, I'm finding out exactly how much they "covered up" with the deep-piled carpet. I guess if you can't do it right, then you have to cover it. Same way a good coat of paint and wallpaper can cover up bad drywall installations....
Of course, I guess they could make the argument that all the gaps where the walls meet the floor and in the entrance stairwell are there to allow for flexing while traveling.....
1999 Holiday Rambler Endeavor, 36' Gasser
Triton V10, Ford F53 Chassis
-----------------------------------------