I would say "vaper" is much easier to use and in the context of conversation, it would be noticeable whether someone meant "vaper" or "vapor." The term "vaper" is just more comfortable to use.
As for the smoker vs. non debate, a vlogger I follow (IndoorSmokers) postulated that even if we are technically non-smokers as vapers, our pasts as smokers shouldn't be discounted. That is, we are on a pure technicality, still smokers even if we have completely abandoned analogs. With this sort of mentality, we can relate easier with smokers, rather than holding an air of superiority or establishing an awkward schism between the two.
It isn't so much about how much you vape or whether you abandoned analogs. It's the community that builds and creates and advocates, and welcoming smokers at their pace (not ours) is something to be respected. You can't make someone switch if they choose not to.