Just to go back to battery replacement a moment, while I do understand that many people, people who perhaps are not as much into the arcane and detailed aspects of vaping, do prefer simplicity and just charging a device with non-replaceable batteries provides that.
However, I think these same people may well change their mind as they get an education into Li Ion battery life when their unit craps out from charge/decharge cycling and they have to send it back to the manf for battery replacement.
Personally, while not a show stopper for me with the CFV, it is a high priority item for me and I would far, far prefer replaceable 18650's. While I suppose built in USB charging circuity would be useful for many who are very mobile with their vapes (can charge from car USB port, for example), added circuity is added cost and added failure modes. Its a trade off and speaking only for myself I would prefer a nice external charger (which I have) and replaceable batteries and can live without built in charging capability.
I feel that way particularly with my Grasshopper where circuit real estate is at a premium and heat dissipation is a tougher problem. Most folks posting about it use external chargers. I think I used the built in charging function once then abandoned it.
This device may well be on my x-mas present list for myself :-)