> Outside of the code, the Ember team's communication skills are top notch. I feel like every time I tell my team that "XYZ is coming down the pipe", there's a clear plan of attack and any impact is minimal. In the last 3 years, I've never had to tell my boss that development will be paused to focus on a refactor/upgrade/maintenance.

Really? We had the exact opposite experience with major upcoming refactors that were poorly handled. Deprecating controllers, adding routable controllers, multiple changes in the rendering systems (handlebars, htmlbars, glimmer), and lots of confusion around coordinating release of core, data, and cli.

Enjoyed most things outside of that though. Learning curve early on was rough, but now it seems a lot better and looks they are rallying back up for good improvements after the 3.0 release.