I use service A for domains, service B for DNS and service C for emails.
To bring it back on topic, this made it easy when I switched service A from Gandi to something else a year or two ago because a few things I was seeing from them "smelled funny." I don't remember the details, just that I wanted to switch.
Anyways, if you don't have a specific reason to pick any specific nameserver go with the easiest one or if you want to have the most features and portability go with Cloudflare.
Even run a dyndns script to have a subdomain for my wireguard connections to home.
There’s nothing stopping you from paying for service with a DNS provider for a domain you don’t own, but nobody will actually query those nameservers for your domain, so it doesn’t matter.