my biggest gripe with NextDNS is not having an ability to add custom blocklists. I'd gladly pay for it even if there was a paid tier with this feature.
So atleast there's that.
I'm currently using Blocky as my DNS resolver. It works fine and is super fast because of the fine control over caching, but I'm disappointed with its memory footprint. 400MB for a total blocklist of 1.3M domains