Regarding the concern of a "great mass" of dots: league members could be represented by smaller icons, that are semi-transparent for example. It would make individuals harder to find and click, but it would make spotting an entire group easier.
Regarding "leagues are for location-based activities": maybe, but let's not confine ourselves to the only examples that pop to mind (OPs, NPC hunts). The entire group does not have to move as a unit at all times. For supernodes it is quite possible to see groups getting split apart, and moving chaotically. It may be helpful to find, for example, the members of another small team that got fully wiped some 400m away from your fight.
Regarding "leagues are for location-based activities": maybe, but let's not confine ourselves to the only examples that pop to mind (OPs, NPC hunts). The entire group does not have to move as a unit at all times. For supernodes it is quite possible to see groups getting split apart, and moving chaotically. It may be helpful to find, for example, the members of another small team that got fully wiped some 400m away from your fight.
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My home is always sweet Yrkanis..