I basically never watched Enterprise. I'm looking forward to giving it a chance. I'll probably give Voyager another chance too, although I did not like the show originally any more than the next guy.
Next Gen is one of my favorite shows of all time. I don't love everything about it (Where are the other 990 people on this ship? Why are all admirals douchebags?, WTF is with Troi's accent?) but it has some extremely good storylines. Easily the most intellectual show to debut as first run syndication. Shaka, when the Walls Fell. Warp speed limits. Inner Light. This is some amazing shit here.
DS9 though....gah, I f*cking hate that show. I can't say I've really watched all that much of it, but I gave up when I realized it was the most racist thing I've ever seen. Its a racist's dream in the sense that they had to invent all new, non-human, races that were, according to the plot, the most genuine racist characters ever. Why invent characters when you can invent entire species who's behavior can be accurately judged just be seeing the starship they are traveling in?
To be fair, this shit really began on Next Gen, but it was rarely the purpose of an episode, or a full season plot arc for that matter.
All shape shifters cannot be trusted.
All Klingons are basically animals (how the f*ck did they ever invent warp drive, or even the wheel for that matter?)
All Cardassians are basically evil as shit.
All Ferengi are basically a Nazi propaganda cartoon's depiction of a Jew. This one gets me the most. Its...extremely grotesque. An entire race where every single one of them is a greedy, thieving, amoral liar. How convenient for the writers.
And humans? Well humans are just "normal", of course. Some are violent, some are thieves, some have extreme hatred for other species, but it is rare. Everyone is different and within "normal" parameters, which is exactly how short-sited racist people see themselves in the universe. Meanwhile you can pretty much make a color wheel sort of thing showing which races hate which other races. Its ridiculously simplistic and lazy on the part of the producers. I mean, its one thing when you are doing this sort of thing in Lord of the Rings, where individual character development takes a back seat to massive world changing concepts and wars in a non-enlightented society with evil wizards and shit, but on DS9...I can't understand why Captain Sisko doesn't have a boombox that launches photon spears.
Then you take all these racist characterizations and bitchy ER-esque dialogue and cram them into the same smelly space station and watch them fight. Congratulations, you've made Star Trek dystopian! Next Gen was all about cosmic phenomenon, robot rights, alternate realities, god, etc. DS9 is about money and revenge. What a bummer.