Well any paid relay you join will be great at preventing spam since spammers don't like to pay. Nostr.wine is a pretty good one. They allow you to filter your feed. Theres a bit of a learning curve there. I think strfry relay implementation are good with spam prevention as well. Eden.Nostr.land is another good one I know of. I run a public strfry relay you're more than welcome to join wss://nostrpub.yeghro.site add it and try it out. Also a paid relay if you're interested

wss://nostr.yeghro.site