Personally I would love to see a HD Duramax between the 3.0 and 6.6. I don't really need something that tows 30,000lbs. If you could get me a smaller Duramax rated for say 15,000lbs, but got 25 MPG highway empty, I would definitely sell my 2020 Duramax for that. Most likely there is not enough price difference between the gas and current diesel to justify a smaller diesel, but a guy can dream.