Age Of $igmar & Alliances - A Few Thoughts...

Age of $igmar took an interesting turn over the last few weeks with the Fyreslayers entering the fray as their own faction who can (for all intents and purposes) be used by any of the "Grand Alliances". The Grand Alliances is a larger grouping of how Races and Factions march to war.
They were always part of Age of $igmar, but now Games Workshop have updated their site to show this more explicitly, which certainly helps when you're trying to work out who goes where and why...
There has been talk of more factions, like the Fyreslayers, who could be used by all the Alliances if the price is right or some other form of inducement is made to join their army. It certainly opens up the idea of army building! In this new Age of $igmar, you could effectively have Beastmen units in the same army allied with Fyreslayers - IF the Beastmen had enough ur-gold that is... and knowing them they would be able to steal enough.
As far as alliances go that break these Grand Alliances, I wonder if you could have a Wood Elf and Beastmen alliance? I like the idea of these Guardians of the Forest against human encroachment or maybe Undead. How would these guys align considering Beastmen are Chaos?
As much as the Grand Alliances seem like a good idea, what's with the Dark Elf and Elf alliance? That seems really odd! They have been mortal enemies for ever and a day and now here they are holding hands. The Dark Elves seem more at home in the Death Grand Alliance to me, or like the Fyreslayers being guns for hire - pirates per se!

So what do you think of the Grand Alliances? Have you fiddled with them? Have you found some holes that don't quite make sense?
​Keen to hear your thoughts...