I would say the Ford Ecoboost has shown us what is in the future. It appears they have been able to design a turbo charger that can be used successfully with a gas engine.
If they are able to pass this on to a 6-7 liter V8 then the current diesels will have some serious competition.
The main thing that gives the current diesels the performance edge is the turbo charger. Remove the turbo charger and you would not see very many diesels is use in the light and medium trucks.
A Chevy 8.1 with current injector technology and a turbo charger would give more power than any current motorhome would ever need.