Minimising time to first render/interaction is on the list what is important for Glimmer. I don't see how this is compatible with moving the conversion engine to the client.
(Not to mention that the app size zealots will eat you alive)
(Not to mention that the app size zealots will eat you alive)
(No Glimmer there yet, only full Ember, but you can get a feel for what it can do, how it is like, test a things out...)