GitHub User: onehouse
This has been my experience as well. I've tried to move away from Rails in favor of a lighter weight solution on a number of occasions. Each time I've ended up migrating back to Rails at some point because of some feature(s) it gave me out of the box, or for some feature(s) provided by a plugin/ gem designed to work with Rails. The two biggies in the last project I did this with were the asset pipeline, which works really nicely with Backbone (especially with the eco template gem), and Devise for authentication.
Thanks for covering this, Ryan. It's a bit of a divergence from the beaten path with Rails, but I think this is the future of web application development.
I've spent quite a bit of time coming up to speed with BB lately, including a 2 day training course with the Gaslight Software guys (I'm not affiliated with them: I highly recommend their course).
Initially I struggled with the fact that using BB (or any of the other similar libraries) means writing a lot more code. It's simply more complicated, especially when dealing with data persistence. Writing basic CRUD operations in plain Rails is pretty straight forward. Involving BB in CRUD is a lot of additional work.
My "ah-ha" moment came when I deployed my first BB/ Rails app to a development server. The performance was amazing. Making JSON requests via AJAX in the background (especially if you're caching) is so much more performant that doing page requests. And, pushing a lot of the application logic to the client is a big win in terms of server load.
I've come to the conclusion that BB is really amazing for client facing front end stuff where performance is a concern. It's less useful for backend admin stuff where simple Rails based page requests provide adequate performance.