As a big fan of the Ars Goethia, I'd suggest going with the term ''Key of XYZ'' for the archetypes name. The ''Key'' you use/chose (aka how you deal with the Vestige) indict, in-fiction, how and why you manipulate the Seals of the Vestiges.
Key of the Demonologist (Constantine)
Key of the Ghostwise (ghostbusters! or shaman, I see dead people etc)
Key of the Incarnum (summoner)
Key of the Stars (Chtuhlu Mythos, 4e star-lock)
and I'd vote for an Int class. Its all about making intricate and complex Seals to bind weakened Powers: even if your tough, even if your a smooth talker, should the Vestige break the Seal and somehow recovers from its bound state, you are dead meat. Only someone with a perfect understanding of the hermetic knowledge of binding has chance to reach level 2