Numerous people have posted about how there should be more custom domains available for the six users included in a Family plan. I agree with that, but I'd even be happy if I could pay extra for more domains. I'm on Proton Business with my fiancée even though I'm not actually running a business, and you can add additional domains beyond the 10 included for a couple of dollars a month, but if I were to add our kids, who barely know how to use email yet, it would double the cost to over $500 a year for the four of us. The family plan makes WAY more sense for our use case, except that I already have almost ten domains registered to my business account just for my fiancée and I. If I could pay to add more domains to the Family plan I would switch in a heartbeat, but maybe Proton doesn't want that because I'd be paying less per year...