From there, for sure, the risk increases. I am not sure I trust DNSSEC to help me much. That said, I rotate through many local recursors at each location, so they have to rewrite my traffic right as it leaves my node. That is doable, but that isn't really what I am defending against. Anything I care about, I validate in a script and write into /etc/hosts.

You are correct, there are not that many recursors that support TLS.

Beyond that, things like software updates I don't trust DNS at all and certainly not public mirrors. I validate packages with GPG signatures. Even that is tricky, because chicken+egg, so I validate the GPG sigs from trusted sources.

On a funny side note, you would be surprised how many people rely on trusting GPG keys that are contained in a package, signed by those same keys, in the same repo.