I've watched most of the Berlanti-verse shows. Of those, though "Legends of Tomorrow" seemingly received the littlest fanfare, for me it was one of the better ones.
The Legends of Tomorrow are a team of powered or skilled individuals charged with protecting the timeline from forces that would alter history. Though the make up of the team changes over the years, the Waverider is most commonly captained by Sara Lance (Caity Lotz) aided by the onboard A. I Gideon (Amy Louise Pemberton). Over the years relationships are formed, sacrifices are made and the world is saved, a lot.
I think the reason I liked "L. O. T" was that, whereas I think that the other series have fallen into a formula and are repeating storylines, the production staff decided, astutely, that if this was going to have an impact it would have to become different. So, without sacrificing the depth of some of the characters they changed the genre of the show to embrace much more knowing comedy and a variety of wilder ideas, which was very much to the shows benefit. Admittedly, if you were starting the show now, you'd probably still have to sit through those relatively dour opening seasons before getting to the better later seasons. Once you do though it's a relentlessly inventive time.
I do think, perhaps, it's only good comparative to rest of the shows in the Berlanti-Verse and is still several steps below something like "The Boys". The time travel idea is well utilised across the run, even if, sometimes perhaps the budget doesn't stretch to the time recerations. The characters are a mixed bag, I'd imagine that everyone would find some to root for and some they would hate. It does bring back Matt Ryan as John Constantine though, and, whilst still not exactly comic accurate it's closer than the Keanu movie was.
If you only watch one series from this universe (and Titans isn't available) then this is for you.