I would have to agree that the show as is needs some revamping to "freshen" it up. By now we all know the drill.
My suggested changes:
1. have a male and female winner. the whole season is set up this way, why change at the very end?
2. rotate couples and assignments every week from the beginning. Using a spreadsheet, this is easy to figure out (don't ask me how I know this

)
3. For Top 10, extend solos by 15-20 secs. Let us really see what they can do (and yes, if they are supposed to dance in their own style, then the ballroom dancers should be able to have a partner!)
4. Here's a radical idea: viewer's choice week! Let the viewers vote on the style for each couple. That would be FUN!
I'm sure I have plenty more ideas, but you get the idea!