Absolutely. The SOA record is important too, to cover queries not taking the happy path. However, once I comform that everything is working alright, I crank up

Absolutely. The SOA record is important too, to cover queries not taking the happy path. However, once I comform that everything is working alright, I crank up TTL to one day to reap some performance gains. For sites with low visits, and likely to not have the DNS query cached, the query latency can add up, and sometimes goes as high as 100ms if the recursive resolver has to take several round-trips to resolve the whole domain chain at EDNS level.