Of course this is merely my own experience, but from this point of view, starting a guild and wheeling it forward, first of all means, to set up stuff, to organize events, be it events for particularly own members or even to the entire playing crowd. Organizing something like this can mean a lot, time, effort and focus.
I agree, it might depend on the time left - 24 hours in total, not more not less. I think there is a limit, or better, a balance to be found, between number of members to be taken care of personally and organization. For one it might be 10 members, for the next one 100, but still, with growing numbers a leader turning into a commander would be mandatory.
But even in the last case, an ambience, in my definition, might be uphold by subordinaries.