So I can find holes in all of the alliances where they don't make sense from a lore perspective.
But, ignoring how one might tie rapidly changing allegiances into the main TES story.. what if?
What if during the development of an expansion, not only does new stuff happen and get added, but political drama cause old allegiances to sunder, and new fragile alliances to form?
The main power blocks could be reshuffled, and/or cause civil wars in some of the factions like what happened in skyrim.
This could add a new sub-faction loyalty. So I am first a Khajiit, but I fight for one of the 3 major power blocks. But if those powerblocks split up and reform, I am still a Khajiit, but my racial allies might have changed.
Just an idea.