So wholesome to see people still discovering this great series... Arguably the peak of TV science fiction, and a "relic from the past" of a period of time where we looked fondly to the future, rather than fearing it...

Deep Space 9 and Voyager are also great "sequel series" to this, albeit both with equally shaky Season 1 starts.

However, I'd recommend putting a lower priority on any "trek" that came after. 21st century Star Trek has been overall pretty low quality (ironically enough). In the 00's we preferred speculative fiction about Hobbits, in the 10's it was all about Sexy Targaryans and Zombies.

There are some hits here and there (Firefly, the Expanse, etc) but overall this century has been something of a dud for good episodic Space sci-fi.