We are most certainly concerned with language complexity. We will only add features that mesh well with the Go we know and love, not just for the sake of utility (every feature is at least useful).
That's good to hear, but it still raises the question of what you're spending your time on. :) I imagine that all the low-hanging GC-related fruit has been plucked for 1.1, so what are users clamoring for now? Without a maximalist attitude, do you foresee a point where the language is declared as "done" and all the full-time devs just pack up and move on?
At this point there are something like 600 open issues, so I think that will be a while.