I would likewise prefer NPCing the absentees for the time being.

In the longer run, I think we need to fill out the group somehow. Rather than new characters though, perhaps we might see if someone is willing to take over the existing ones? Player takes over Kara or Solomon, and can make a few tweaks to suit them without changing the major details. It doesn't seem like its healthy for an uratha pack to have too much turnover

P.S. How do you want to handle the taming mentioned?