The critique of "sequentialism" resonated with me. It's like the traditional way of navigating where you have a map and a route and just go step by step. But that only works if the terrain stays put! These days I think navigating as a faith community is more like flying your moving spaceship through a field of randomly drifting asteroids. There is no "path," and if you start trying to chart one the asteroids will have moved before you get it finished so it's obsolete before it's done. Navigating in this environment is, I think, done by quick orientation followed by incremental movement, then repeat. And orientation means knowing what's right next to you as well as where you ultimately are trying to go.
In practice, I think that calls for the listening to God and each other that others have mentioned. We Refresh our awareness of where we are and where we are going, then Respond. So the path forward isn't laid out in advance as a sequence A to B to C to D etc. Rather, the sequence is replaced by a discipline: "(Refresh, Respond) Repeat."
I think, if we do that, then the original question about community vs. mission gets answered over and over as God leads.