Wait a year or two for the new Ford 7.0 and see how it is, but in the mean time, that old diesel would be a better choice than the new ones with DEF and PF regens and all those new goodies, unless you do the Delete.  I wanted another Diesel but just couldn't justify the higher costs of the oil, def, and fuel consumption. Wish I had kept my 99 F350 7.3 now.  Stuck with the 3.5 EB for now as it is a beast and tows what I have now comfortably with ease, though it does suck the go juice, 7 MPG towing, but 18-20 without towing makes up for it. Over a million of them made, and the Gen 2 has even more power and torque. 
The 2019 Ram 1500 is a nice looking truck, they did a good job, and may update the 2500/3500 too, but until then, will wait and see how they do.