We've come full circle and have just pulled our stack back from a complex framework (Durandal, akin to Angular) to a simple architecture centred around knockout.js, and everyone is happier for it. The code is cleaner and debugging is a world apart.

Backend wise I've taken a liking to Express because it hides nothing. I prefer it over Rails or ASP.NET MVC, where there is so much magic. I would switch if I could but we have too much legacy code.