If you are comparing a "Super C" to a Class A diesel pusher then I would say you do not get the same "space" for the length of the motorhome. The 4-5 feet of engine space sticking out the front of the Super C is wasted area as far as living space.
Since this truck was originally bought by a retired owner/operator who had owned several big tractors that he wore out while working as well as 3 that he had on the road at the time of his retirement, I figure that this one was pretty thoughtfully chosen. He bought mine after he retired and was fulltime and about 5 years later began to have dementia issues. Before he got too bad he wrote out very explicit instructions for his wife on how to properly care for it and she followed those up to when she sold it to me, several years after he passed. I bought it in 2014, with 98k miles and have mostly used it to tow our 4000# travel trailer, since then, bet we only travel seasonally so in the winter season it only gets driven for occasional trips. Now that covid has cramped our style, that 35 gallons of diesel is lasting a lot longer, which is the reason that I got to considering an algaecide for it. The independent diesel mechanic that I take it too says that it has one of the best engines that Cummins ever put in a small truck and has told me that should I decide to let it go, he wants first crack to buy it. I thought that I'd also talk to him about the subject and what he says it is pretty similar to your opinion. I expect to keep this truck as long as we keep the travel trailer.