Ok, reposting since I changed my original post:
I suggest:
Order of the Three
Why?
'Order' to signify that we are disiplined and have explicit goals, and to some extent spiritual - we share a very long history on Rubi-Ka and care about the planet's future, as well as its turbulent past. Disicpline and spirituality combined can be powerful tools.
'Three' - apart from the obvious number of merging guilds, it brings a vague association with a certain ancient cult Adds some mystique and provides a link to ingame elements.