My experience is only limited on the Renegade Verona. We have few corporate owned ones from 36' to 40'. Freightliner M2 with 8.9L Cummins and Allison 3200 6spd trans, 8mpg.
Ours are loaded to 32-3300lbs, it's struggling with power and braking on the highways in some western states, AZ, NM, etc.
I would imagine it would be under powered with the 6.7L.
8kw Onan QD gen set is a must. Stay away from marble floors, stick with LVP, it would be lighter and cheaper to maintain. Plus marble floor soaks up all the heat, hard to keep warm with hydronic diesel heater and heat pump.
I really don't care about the 150gal freshwater tank, too much of weight penalty on the road.
I've had more troubles with Lepert/Schwintech slides than the Liftco slides.
I've been to the factory, they all built like shit.