I think that is not practical. They are bottled up inside a single solar system at the end. If Cardassia prime had enough resources to (own its own) outproduce the shipbuilding of the Federation and Klingons and Romulans, they would not have got buck broke in back to back wars against the Federation and then Klingons. You can maybe handwave some of that away with superior Dominion tech, but it's not magic. They are still resource bound like everyone else. Yes they would rebuild their fleet and it would be even more painful to conquer the longer it went on, but there's no way in hell they could use the resources of a single world to produce more ships than the ~150-200 worlds the Fed/Klingon/Romulans were producing in total war mode.