Which tests should I run to see if everything is "the best it can be"?

Hello,

I configured SPF, DMARC, DKIM and installed latest version of PHPList on my private server, everything is configured and everything seems to works fine.
I would like to run some tests to determine if all the things involved in email sending are ok and correctly configured. It’s important to me to avoid technical mistakes which would make my emails quickly categorized as spam. I’m not a spammer but I’m working for artists, for which newsletters are important…

I know mail-tester.com. Is there some other tools to ensure that everything is “at best” in my emailing tool ?

Many thanks for your advices,

T.