Yeah, Momiji winning it felt weird, considering she basically copied Yun concept and Hazuki explained earlier the reasons why Yun should have been picked with how close their design were (being the one who came up with the idea, having more experience and so on). Heck, even Momiji felt she should have lost this one.
It really feels like Yun was robbed of the victory when she's the one being the whole urban style/turf war concept, but I suppose this is the lot of being a secondary character when the author was focusing mostly on the Aoba/Momo rivalry... The fact that she was the first eliminated when she actually brought the project this way was frankly unfair in my opinion.
Personally, I think it would have been more interesting for Yun to win this : it would have given her a boost in confidence that she really need, seeing how she feels stuck in her career and forced both Aoba and Momo to stop for a while and consider why they lost this one, giving her more chance to grow outside of having someone to be a rival.