^New ship designs will never happen. After all it would add to the cost.
Not really. We have literally years, maybe even a decade, before DS9 seasons 6 & 7 will be remastered. That's plenty of time for some talented visual artists to come up with new ships if they wanted to, at minimal cost.
I'm not sure why you would want to replace the First Contact ships. They were brand new ships at the time.
I want to replace them because I hate them. It's as simple as that.