In the Cities, we have supergroups (guilds) with 75 member caps. Do y’all have caps in other games? ATitD required you to pony up more bricks and boards to increase the guild cap, but I cannot recall caps in other games. I cannot imagine that in WoW, with 40-man raids and a 75-man cap. The 75 cap might have related to something at some point. I recall the claim that it was needed for supergroup PvP raid balance, or to prevent massive lag in said raids, but since said raids are two years late with no plans to implement them, it is just annoying to have alt supergroups into which to shuttle characters.
Am I mis-recalling the normal estimate that 1/5 of your subscribers are online during peak hours? That would mean a full CoX supergroup, with no alts, would average 15 members online. This is about two full groups, which is quite enough for a game that only recently added its second raid — there is not much to do with large groups. In our glory days, I recall our Teamspeak setting up rooms because we were running two full groups at once. We never went past that, despite a massive flurry of activity.
This seems like a combination of guild and game design. Your guild caps at 75, so your active guild playerbase caps around two full groups; letting alts in caps you around one full group. Since the full group is the standard unit for task forces and high-end play, that all falls together.
It all falls apart when people leave. You have an alt SG for alts, an elite SG for folks’ level-capped characters (now alts), and the main SG. Conveniently, you can communicate in a coalition channel or a global channel across the lot of them. When people leave, though, you are already that fragmented. You may only have a dozen members in these SGs, so any loses can kill the whole thing. Now the surviving members are spread across three guilds, each of which is a collection of alts and ghosts. I know one SG that made a half-dozen alt SGs for the various hero classes, then ended up with only a few active characters in each after the next wave of MMOs came out. Do you abandon the old base and everything that went into it? There are a lot of orphan supergroups out there, inhabited by long-dormant alts.