Agreed. The point of distributed DNS is to prevent a single source from being overloaded. Cloudflare's whole business model is distribution and redundancy.
Unless you have local domains to resolve (if working for a corporation, browser configuration should be locked by IT policy anyway), why would you ever need your own copy of the DNS registry? It's not like there are allowed to be different public DNS registries, the entire internet would just burn in the resulting chaos (as happens occasionally when a major DNS power screws up).
The only problem with a single source like Cloudflare would be if we didn't trust Cloudflare to show us the page we wanted. It sounds like Cloudflare, being a ""trusted recursive resolver", is willing to be open enough to show this isn't really a concern.
I'm much more worried about what my ISP is choosing to do with it's man-in-the-middle status.