*Since I don't have the M1 chip, does that mean I won't have access to Universal Apps?
Universal apps have both an Intel and an Apple Silicon run-time. You will be absolutely fine on an Intel Mac with or without universal apps - all current apps are Intel-only, and universal apps will stilll run on Intel.
As for "when you should you upgrade", I am a long-time believe that you should wait at least a few weeks to a month after release on a machine y ou depend on working to see if there are any major bugs in the release. Last year with Catalina lots of people had problems with Mail, for example (it was with mail stored locally on your Mac as opposed to accessing mail on a server.) But things like moving messages from one location to another would not actually move the content of the message, and the original would be deleted, so the message would be lost forever. And Apple wouldn't certify that you could restore mail from a Mojave Time Machine backup to Catalina. I just installed Catalina a few weeks ago myself, on only one of my Macs, and so far, everything is fine for me.
So far I haven't seen any major issues like that with Big Sur being reported.