Darkwing, your info is incorrect. From what I remember -- and we're talking about something I read probably ten years ago, so make what you will of it -- they did toy with the idea of the Federation losing the war, but something miraculous would happen at the last moment that would defeat the Dominion, or some such nonsense. I don't think there was ever any serious talk about ending the series with a triumphant Dominion, and this was definitely not planned on leading into another series.
This is what I remember reading as well.
To be fair to Berman, Gene Roddenberry would have had serious problems with 1 and 3 as well.Looking at the show from King B's perspective, it broke all of his rules: 1) it had characters in conflict WITHIN the primary cast 2) things that happenedin one episode MATTERED in future episodes 3) it wasn't afraid to portray the characters as less than "perfect people".
I doubt Berman would have had problems with any of that (at least to some extent).
Wasn't the reason Berman and Piller made DS9 "co-owned" by the Feds and the Bajorians so there could be conflict on the show between characters and still keep it within Roddenberry's ideal future?
I remember in the Making of Deep Space Nine book, they were interviewed and they mentioned that the Starfleet people could be all perfect with one another, but the Bajorians are a different story. They are not Starfleet, so they don't have to be perfect, nor do they have to like Starfleet. And thus we have conflict. B&P were able to eat their cake and kept it too!
They used that same loophole with creating Voyager, but UPN killed that show's character conflict that right off.