I love the Quad system too. But should the Big Sky add the other 3 Dakota schools to make it 15, they need a 16th member to have an equally 4-quad 4-team system. But which of the fb-affiliates would you prefer for full membership? UC-Davis or Cal Poly? Sadly, former Big Sky member Cal St.-Northridge no longer sponsors the sports after leaving the conference to join the Big West (which at the time started to drop football). And here's an interesting format under the quad system (at least for some sports like basketball):
Dakotas (East): North Dakota, North Dakota St., South Dakota, South Dakota St.
North: Montana, Montana St., Idaho, Idaho St.
West: Eastern Washington, Portland St., Sacramento St., Cal Poly/UC Davis
South: Weber State, Southern Utah, Northern Colorado, Northern Arizona
But to New Mexico St., I believe they would be a great addition for non-football sports, with basketball being improved. Plus, the closest travel partners for the Aggies would be Northern Arizona, Northern Colorado and Southern Utah.
When I came up with that scheme back in May my thought was that the 3 pods of 5 for Olympic sports was a tenable arrangement and then for football Idaho would continue playing FBS ball in the Sunbelt thus making the football quads:
ND St, UND, SD St, and USD
Montana, Montana St, E Wash, and Portland St
Idaho St, Weber St, S Utah, and N Colorado
Sacramento St, UC Davis, Cal Poly, and N Arizona
If Idaho wants to play FCS in the Big Sky it probably necessitates taking a 16th member (NMSU?) or jettisoning the Dakota project.
Like I've said before, I think the Big Sky is a conference that could actually benefit from losing members. Letting Sacramento St go to the Big West and getting UND into the Summit/MVFC would really help consolidate the league.