Thank you all for the replies (and free entertainment with the back and forth, ha)! He does want to quit smoking and get back on vaping so I have a feeling that he will stick with it. He wants something with a looser draw (in comparison to a cigarette) so that's why I was leaning towards the nautilus line with the BVC coils, as I have heard lots of good things about them. He also likes the size of the mods that I usually take when I make the trip out there to see him (IPV2 and Stingray x clone always in 18650 mode as I like to sub-ohm). Obviously I am not going to toss him a mech and RBA or RDA right out the gate and I haven't checked out his local B&Ms yet so I can't speak about what they can offer and if they would be helpful at all. I have a feeling that it would be best to just take him shopping at a local shop and see what he likes, rather than surprise him on Christmas day with something that he doesn't like. Only problem is that I may walk out buying more stuff for myself on top of his new setup haha.
Another thing you may want to consider is the long-awaited MVP3. It will come with Evolv's DNA chipset and I have a feeling that it may be completely redesigned. It's widely rumored that it will be released before Christmas, but nobody has a date yet.
Innokin Announce MVP 3.0 – Vape Mile
If your dad wants a mod with a replaceable battery, I own and like a mini ProVari 2.5 and a mini ss Sigelei Zmax. There are many good regulated tube mods out there, but I honestly believe that those little but powerful DNA boxes are the future of vaping.