Agree with both
@Huntn, and
@SandboxGeneral had to say; I saw TOS as a very small kid and adored it; then - yes - watched re-runs as an adult.
In common with
@SandboxGeneral, it took me a while to get into TNG, and, when I did, I became completely captivated; to my mind, this is probably the best of all of the Star Trek franchise.
I watched the first two seasons of DS9, and found it tedious. Then, I moved elsewhere for work, and lost track, - and, more to the point, lost interest, too - and never ever got back to it.
Friends and cousins who were into the Star Trek universe assured me that the last few seasons became brilliant; and I believe them, but I have no idea when and where that brilliance starts and - unless it is pinpointed for me - have no real desire to look for it.
Re Voyager, I liked the idea of a female captain, but never really warmed to the series, though I watched most of season 1. Enterprise, I frankly loathed; again, I read that it got good later on. At this stage, I almost don't care: why will they not learn the lesson that if you serve up boring tedious tripe (poor character development, boring, unintelligent plots, uninteresting stories) for the first two or three seasons, you will lose your audience.
One of the things that worked really well in TNG was the fact that the series (and, granted,, not the movies) was a genuinely ensemble piece of acting: All of the main cast had at least one show per season - one story per season - dedicated to them. It allowed the characters to grow with the show, and meant that you really felt you knew the crew.
However, with some of later series, Voyager an dEnterprise especially, - the minor characters never really got he character development that they may have merited, which lead to a shallow story.
Thus, I never felt that I knew the crew of Voyager, or Enterprise, other than one or two other than the captain; in fairness, DS9 was different, and I am sorry it took so long to warm up that I lost interest long before that happened.
As the various other series wound on, frankly, the idea of the producers that you should trim it down to focus on two or three main characters made for very predictable and shallow and limited plots.
Anyway, as I am in Europe, the whole topic of a dedicated channel is sort of moot, but I must say that I really loved the first two Star Trek series; fantastic, creative, intelligent thoughtful TV at its best.