I made an alias for River and changed his build a bit* and fleshed out his Q&A a bit more.
* I'd used medium armor which doesn't work with battle dance and had too many background skills - there's a bug with herolab's gestalt add-on and that.
They don't fit the story I have in mind for River but I noticed a things what would have provided nice synergies: A muse-touched assimar would have given +2 on perform (nice with versatile performance) and have cold resist 5 (among others). Fey Foundling would also be awesome but that's because it's brokenly strong :)