Well, at least they didn't dump Jake Sisko, they didn't turn him into a psycho who were planning to kill everybody on the station, including his father and they didn't turn him into a whimpy wreck determined to go home to Earth to live in a cave either.
That would be incorrect. "The Reckoning" & "The Visitor" or "Nor the Battle to the Strong" both of those things happened to Jake.
Not to mention that they didn't dump anyone when Worf was brought in.
No need to mention it, before Worf joined DS9 only had 8 main cast members allowing them the budget to add one more.
As a big fan of Jadzia Dax while I was sad to see her go, I accept the character is dead and have no problems with main characters being killed off on the programs I watch especially since death of main characters on TV shows is becoming more & more common.