The factions have zero resonance or interest to me right now.
Here's the extent of my current knowledge:
Empire, bright happy tree huggers. Kingdom, gloomy emo tree choppers.
Different ridiculous hairstyles, different monster friends... a few different buildings, and Death/Life magic. That's about it.
Faction to faction specific differences? Got me. Resoln are extra gloomy and Altar are noble goons I guess?
MoM/MoO/HoMM/AoW all used various sci fi and fantasy tropes to create instant recognition (and it worked). Elemental doesn't have that for me. Come to think of it, GC2 suffered from the same problem.
Fall from Heaven created resonance with a unique backstory and very, very distinct factions that had unique units, spells, mechanics, and identities tightly entwined with their gameplay - necessities for 'selling' a handmade world.
This is much more of a meta-issue than the far more pressing gameplay and technical issues with the beta, but I think it has more far-reaching consequences as far as immersing new players in the game. It affects the writing everywhere, and also quest design, faction specific technology, hero traits, spells, equipment, abilities, and so on.
I've read various descriptions on items, heroes, leaders, quests, and so on, and while the general quality of writing is better than WoM was by far, there's still not much in the game that's making me care about the pre-cataclysm N'ther'qirkians and their blood feud with the Balkinzixes (paraphrased).
The biggest impact the overall story of the Cataclysm has had on the game for me is: 1) Making me hate the amount of boring brown terrain in the game 2) Generating counter-intuitive mechanics like Imbue Champion 3) Making me fight a lot of really boring wildlife in the early game.
Even the civlopedia still has the absurd name of Homonnomnom.
Anyway, just musing. The gameplay/technical side is much more important, but I'd be curious to hear how many people are being 'pulled in' by the FE world as it stands now.