Northstar & Alpha Flight? I like the idea of having Northstar being included in a volume 5. However, if Northstar is the major character, then I have to note that Northstar has already had his own mini-series (in the 90's), Northstar and Aurora got a huge amount of page-time in volume 4 (to the detriment of other characters), and vol. 4 was different from vol.3, which was different from vol.2, which was different from vol. 1.
Without taking it to OMEGA FLIGHT mini-series extremes, a roster with some recognizable characters and maybe 1 or 2 new/not-usual-to-Alpha Flight characters is what I would like to see.
OTOH, if a particular Alpha Flight character is to be high-lighted, Northstar appears to be the logical choice. He is the most high-profiled member.