I definitely agree. I think they did better with the show than I could expect. It had a lot more "Trek" to it than you would expect from a show centered around a deep space station that orbits a a single planet in a star system where only one sentient species makes its home (if you consider the Cardasians that made their home on Bajor artificial...like I do...and the Bajorans do, lol!).
Except for the exception of the Borg sphere that crashed on Earth during the vents of Star Trek: First Contact, there is no timeline contamination or anything like that.
But, instead of first official contact with the Borg being 2365 (when Q thrust Picard and crew into the Delta quadrant to see the Borg for the first time), it was 2153 when the Starfleet scientists discovered the wreckage of the 2063 Sphere rubble that had fallen on to the earth during the Events of First Contact.
Here is how the enterprise writers handled the nascent Federation stumbling upon the wreckage of the Borg Sphere: Archer makes a comment to T'Pol that Zefram Cochrane once talked about the nature of the events that occured in 2063 (that a group of people from the future came back in time to save Zeram Cochrane's plans for a warp ship and the Borg came to stop Zefram from succeeding). They say, in the show, that Zefram later retracted those statements and blew it off as his drunkenness talking. Archer remembered because Cochrane was one of his heroes and he read every single speech or saying, ever, from Cochrane so he remembered Cochrane talking about the Borg in that one interview.
I do not know how they keep Starfleet from knowing about the Borg but I do know they wrote that the ship the Borg took over in that episode in Enterprise sent out a subspace transmission to the Borg in the Delta Quadrant and it will take 200 years to reach them. Thus perpetuating the events of First Contact because that is when they Borg will come back and attack earth to prevent them from developing the warp drive.
So did the writers of Enterprise create a closed loop timeline where even the time travel is accounted for and does not create a conflict? I think so. So I could be wrong about timeline contamination.
I recently watched all of DS9 and I have to say that as a whole it's probably the best Trek series. Granted I've only watched a little of TOS and I've only now started to watch Enterprise again (I used to watch an episode now and then when it was syndicated on UPN), but Voyager never appealed to me, and between DS9 and TNG I gotta say that DS9 impresses me more. Mainly for the last three seasons. Speaking of the episode in question, I was really impressed when they didn't just leave it as a one-off and actually made it an important plot point and a part of Sisko's character journey. It worked very well thematically seeing as one of the main selling points of the show vs other Trek series was "we're not going to whitewash--bad stuff happens, even in the Federation." What I really liked about DS9 was the fact that it "looks back." TNG, which I love (mainly for Data and Picard) has this nasty habit of only looking back to Earth's past from a smug, "oh we're never doing that again, thank God" perspective, whereas in DS9 the main question seems to be "well, will we ever go back?" I think Bashir sums it up the best in the 2020s San Fransisco time travel episode where he asks Sisko if humanity has really gotten that far, and if a few things should go wrong could they really stop themselves from becoming like the Romulans and Cardassians. I love that the Section 31 arc expands on this, suggesting that...well...humanity ISN'T so different from the Romulans or Cardassians.
The best thing for me about DS9 is that it dispenses with the ridiculous presentation of Starfleet in other series, where The Federation's military arm is about as militarized as our Coast Guard. I never bought that the Federation could survive with neighbors like the Romulans and Klingons if their military's prime interest is in exploration, and their weapons are given minor emphasis--things like the Defiant, the new gray uniforms, the threat of a military coup, and Section 31 made the Federation and Starfleet believable for me.
I agree with PR, I think the best episode is In the Pale Moonlight. Though I also really liked By Inferno's Light--the scene where the Romulan warbirds decloak and request permission to join the fleet...Sisko sums it up perfectly: "Well I'll be damned." Even the Borg were never a big enough and imminent enough menace where you'd see the Federation directly joining forces with their arguable nemesis.
“Where the longleaf pines are whispering
to him who loved them so.
Where the faint murmurs now dwindling
echo o’er tide and shore."
-A Grave Epitaph in Santa Rosa County, Florida; I wish I could remember the man's name.
Regarding Enterprise- From what I've heard, the Temporal Cold War, the mysterious guy leading the Suliban etc. would all lead to the Earth-Romulan War in the 5th season if the show would've continued and that conflict would've made the Dominion War look like a brief skirmish. It would've been so devastating that it basically forced the formation of the Federation.
Back on topic, I enjoyed DS9 and a lot of people liked it because of the ensemble cast and because it was both darker and more human. I can also see how it really pissed off a lot old fans and Gene Roddenberry's family since it featured a major galactic war between two powers and the Federation/humanity was supposed to be beyond all that and capable of solving any conflict not involving Doomsday machines or giant amoebas or the Borg with diplomacy. I think the Earth-Romulan War was intended to be the last outbreak of total war in the galaxy.
__________________ Land of the free, home of the brave...
Do you think we will ever be saved?
In this land of dreams find myself sober...
Wonder when will it'll all be over...
Living in a void when the void grows colder...
Wonder when it'll all be over?
Will you be laughing when it's over?