8 ft TC, who are good for towing, seldom have showers, so you will need find compromise that works best for you. 10ft might have all the comfort, but than you will have to use stinger.
Boats tow way better than TT so I would not worry about getting huge truck for it, but when you get 10' TC, that will weight > 3000 lb. Add 450lb on short stinger and you are in 350/3500 truck territory where it won't be far to talk dually.
My advice is to see what TC are available in your area and sit in them. Enter shower and see if you can turn around in the stall.