Thanks for sharing your experience. As someone at a place with both ember and Mithril it's relevant to me. Can I trouble you for a couple more details?
Did you use MSX with Mithril? We found Mithril to be usable without MSX but clicked more for people with MSX.
What thoughts do you hear from people who work on the ember app regularly?
No, because it was green-field and I was trying to keep it as simple as possible; having to have a build step to run the MSX tooling was not really worth the complexity.
> What thoughts do you hear from people who work on the ember app regularly?
Mostly frustration, honestly. The main developer (who spends most of his time in Ember, though wasn't part of the team when it was originally built) has more background in Angular, and a number of times has lamented how much easier things are there. Although he's still reasonably productive now, it took months to get to that stage. Everyone else comes and goes, depending on what we're working on, and the general feelings seem to be somewhere in the spectrum between mild frustration and hate.
Maybe another interesting point.. We used to get new hires to start with fixing small UI bugs to help them learn the systems and do something with immediate highly-visible impact. We really can't do that with Ember.
I think if your style/mindset perfectly meshes with that of Ember, and you specifically decide to devote a considerable amount of time (months) to becoming an Ember expert then you can certainly master it and make good use. I'm not sure you'd produce anything better than someone who had the same time and level of mastery of React or Angular or Vue, however.
Did you use MSX with Mithril? We found Mithril to be usable without MSX but clicked more for people with MSX.
What thoughts do you hear from people who work on the ember app regularly?