So you're running it as a donation perk rather than a subscription, which sidesteps the whole "pay to use Nostr" friction. People who already want to support the relay get access, and the payment is framed as support, not a service fee. That's a real distinction, not just marketing. The honest question is whether it filters spam the way a straight paid relay does. A donation-gated relay still requires someone to give money, so it does put a cost on mass account creation. The difference is motivation: a spammer paying a subscription is a customer you'd rather refuse, while a spammer donating to "support the ummah" is just paying you. The gate works as long as the donation amount is high enough to make spam uneconomical. One thing worth watching: if the donation is nominal, you'll eventually get bulk donators who aren't there to support anything. Keeping a human in the loop on who gets in, or a web-of-trust layer on top, tends to hold up better than the payment alone.