The Coeurlclaws end up more tribal because they operate outside of Gridania's laws to follow their 'traditional' hunting practices. Any miqo'te outlawed for this practice gather under the "Coeurlclaw" banner, bound by being like-minded. The less seen familial units of the Keepers probably have adapted their hunting practices to fit with Gridania's laws, so they hunt in moderation, and they are likely 'tamer' and gravitate less to the physical arts and more to the arcane or crafts. As that wonderful article linked above pointed out, Keeper mating rituals are likely more closely related to that of birds and females choose males that impress them, and that's not necessarily physical prowess, and more likely artistic.
But even a 'family unit' is subjective if there is a high likelihood that the males roam from Keeper village to Keeper village... Monogamy is unlikely with the numbers as was pointed out...