I have already seen everything Trek some more than once already. I always get a bit sad on the last few episodes of a series. I am going to miss the characters and seeing them continue to grow and interact with each other.
The same thing happened when I finished my rewatch of DS9. I think it hit my harder with DS9 since that those characters had such a good chemistry with each other.
Once I finish Voyagers I plan to start watching TNG right away. I havn’t done a complete watch through of it for many years. I usually get the first 2 or 3 seasons before getting distracted. I have been looking forward to watching it again.
I agree the end of a series can feel a little draining as the stories conclude. I get that way with books too.
Lots of rewatches of the trek series, and I do skip ones that are boring to me, sometimes I just follow main story arc with ent and voy, but there are some really good bottle episodes that I miss that way.
If it feels like work to watch an episode, then I skip it. Sometimes it’s the topic, or my mood, or life.
Enjoy tng again!