Sorry for the derail, back to Kathy's OP,
So to start with I should say that my decision to try rebuilding comes from two pathways if you get me. The first is for my husband who is blind and who currently vapes on an MVP 2.0 with a mini nautilus. The problem we face with that is he needs someone to check and adjust everything. Advice online on FB groups has been to go down the mechanical mod route for him and eventually find a sealable rebuildable tank. So that is in the back of my head.
I have been giving this some thought.
I think the decision to go with a 22mm mech mod is the right one because any adjustment is in how you make the coil and at what ohm. Then you just press the button and suck.
The next question is, what do you put on top of it?
I really can't see that any dripper would work for him. Once it gets dry he will taste it, he could take the top off and drip without too much problem. But putting drippers back together is a visual thing. You line up the air hole with the coil, you line up the air holes by eye... there may be exceptions where the air locks and the top cap can only go back one way... but I can't think of any.
A lot of people who like a wide drip tip do drip straight down the hole. He could do this if you were around. But, if anything got knocked out of line, he would have to try and put it right by trial and error. It is not impossible, but not the ideal solution.
Next up you have Genesis tanks. These can be a pig to set up and get wicking right. I have re-wicked mine with cotton twice today, both times it worked well for 20 mins then the cotton shrunk and gave me hot spots. This doesn't happen all the time, i can go days without re-wicking. But when it happens you really need eyes. You also have to tilt it towards you with the wick facing you to 'dip your wick'. This is done visually. They aren't for everyone anyway.
So the next solution would be a Kayfun style atty. I don't own one, but i am told, that once you get the knack of building them they are very reliable, can hold a good amount of juice and are great for vaping all day.
The only other alternative i can think of would be an Rebuildable Dripping Tank Atomizer. These work by pressing a button to drip juice onto your dripper. There aren't many of these yet, and they have mixed reviews. It is not something I am ready to spend money on yet.
So I would say a Kayfun is probably your best bet, and there will be people here ready and willing to sing it's praises. He could also have something like the Nautilus as a backup in case it borks when you aren't around to fix it.
And maybe we can convince some Atty maker to design a dripper for the blind? It shouldn't be too hard to put in notches so it can only go together one way, air control rings lock, etc.