I was fairly sold on react/flux after trying it because it is very simple and you can build very quickly. I've been trying Mercury.js over the last week as I thought the 'cycle' of flux/react was a bit more than necessary. Your front-end guy might be sold on Mercury next.
I did initially think the cycle of flux was a bit too much, but since having to have actions be created from various sources, etc, I've come to realise that it's actually a really good balance.
Having a glance at Mercury. Looks interesting, but react is working so well for my projects I'd need a damn good reason to give it up.
He came to that decision just after we committed to angular... :(