Here I will try to "rate" - on a complete subjective basic - some Theme/style Plugins for Confluence 

RefinedWiki Original Theme

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Conclusion: Problably an excellent product, but set of a lot of time to design You style(s). As a private focusing on content rather than nitty gritty design, I gave up on the plugin.

Overall conclusion

No theme can be branded as a winner, for that the Themes are way to different, and each coveres a part of what the need are. Zen is for sure the leading product if You want to go all the way, whereas Enterprise Theme in general is quite "portal" aming. RefinedWiki is easiest for making a quick and nice look in overall, and with a Designer, something the users of Enterprise Theme may miss after a while.