I personally don't think the early seasons are bad. It's just that they aren't as serialized as the later seasons, not delving into the major conflicts of DS9. That's why, I think, they aren't as appreciated as other seasons like 4, 5, 6, and 7.
I think they were in a TNG-like formula for much of the early seasons. And while that wasn't bad, the character and story arcs which became more prevalent in the seasons that followed worked far better for DS9. In my opinion.
^ I agree with both of what you are saying. I myself enjoyed the early seasons and I think that there are many episodes that are excellent in the beginning of the show. The writers and actors grow into their roles and get to the point (season 4) where they become a well oiled machine. It took those first few seasons for them to find there feet and there place without having to rely on TNG.
One thing that the writers did excellently by season 4 was introducing a thread/plot point that they could later pick up on in another episode/season. So as not to look like it came out of no where. I love how they were usually short scenes and even sometimes blink and you miss them scenes. Things like that really helped to shape this show into a serialized format.
The True Way group mentioned briefly in season 4's Our Man Bashir
for being responsible for sabotaging the runabout. They are mentioned only in one other episode and that plot point was never picked up again by the show. But the point is, is that they could have used that as a major plot line further down the line. The seeds would have been there so as not to seem like it came out of no where.
It's revealed in late season 2's The Collaborator
that Odo is in love with Kira. It's a blink and you miss it scene in which Kira tells Odo that she's in love with Bariel and it's in his hesitant response. It's a plot line that lasts the rest of the show.
Plus at that point (season 4) they had developed the characters and their relationships to the other characters. They had gotten into the grove of focusing on particular pairings and built plots from there.
I really enjoyed...
Season 1s: Duet, Progress, In the Hands of the Prophets and Captive Pursuit
Season 2: The Homecoming - The Siege, Cardassians, Necessary Evil, Armageddon Game, Paradise, The Maquis, The Collaborator, The Wire and Crossover
Season 3: The Search, The Abandoned, Civil Defense, Past Tense, Life Support, Destiny, Improbable Cause, The Die is Cast, Facets and The Adversary.
I thought were excellent..
Duet, In the Hands of the Prophets, Necessary Evil, The Wire, Improbable Cause and The Die is Cast.