Which one should we choose among Facebook ads: PPC or pay-per-impression? If I calculate, in my niche, I'd get fewer potential clicks with pay per thousand impressions... However, the PPC variant isn't paying off well enough... yet
The site looks really good. I'd say wait with the PPC model, since it is the one that makes more sense for your niche, as you said. By the way, have you tried looking up other alternatives to Facebook ads? Maybe you can find additional payment models that can suit the site even more.
you should use PPC if you want people buy your product and CPM if you want people to know your product! So choice depend on you!