There are a lot of episodes to get through with any of the 2nd generation Trek (TNG / DSP / Voy)
The way to deal with them is to find an episode guide like this one
TNG Episode guide
Across the course of six or seven seasons there will be a lot of filler episodes you can skip straight past. This is especially true of TNG that was more episodic in nature than DS9 or Voy.
I’d say revisit DS9, it is really ropey at the beginning, as is TNG to be fair, but by the time Worf arrives and Sisko shaves his head it starts to get really good.
Its worth remembering that DS9 was one of the first TV series of any genre to move from an episodic structure to a big story arc, seasons 4-7 are essentially one big story.
I used this guy episode guide when I re-watched it a few years ago:
DS9 episode guide
Overall I put TNG and DS9 on equal footing. DS9 has the better overall story but TNG has the two best characters in Trek: Picard and Data.
If I was to rank the others. I’d probably put Enterprise slightly ahead of Voyager – its aged better and the Xindi war / Temppral War arc at the end is pretty good.
Discovery isn’t proper Trek, its JJ Abrams Trek, its okay Season 2 is better than Season 1 but overall its a bit of a mess, its like each writer had a plot idea and they just used all of them at the same time and almost none of the characters behave like they are in Star Trek. Entertaining enough if you just want the occasional space battle.
Non trek: The Expanse is excellent – takes a few episodes to get going, but Season 2 is some of the best recent Sci Fi I’ve seen. Its also “Hard Sci-Fi” so the is very little in it that’s not based on reasonable science – no warp drive, no shields, no phasers, no / very little gravity which makes it very different to the Trek universe.
BSG is the best there is but it’s a bit more adult in nature.
TL:DR
Watch DS9 but skip most of Season 1 and 2 😉