A Viking: Total War would be utter brilliance, but I doubt it'll happen.
To be fair, the MTW1 expansion was titled Viking Invasion... and heavily featured them
Anyways, I've been a long standing fan of the total war series, having played everyone (except napoleon, oddly). And I must say I've enjoyed every single one. Sometimes there have been regressions in places, but for the most part everything has moved forwards.
The battle AI gets a lot of flak, and for good reason. If you looked at posts in many of the total war forums you'd think the battle AI has got worse since shogun, when in fact really it has got better. It's just the case that everything has has greatly advanced in both complexity and quality... and the battle AI has only stumbled forwards a tad.
On the plus side, while the battle AI hasn't improved much, the diplomacy/strategic AI has massively improved in my experience. Take alliances and diplomacy in general. In stw it was literally meaningless. In mtw1, it would sometimes seem to have a tiny effect, but generally did nothing. In rtw it could sometimes make an impact, but was still erratic and often defied logic. Now mtw2, it started to make a lot more sense with far less illogical backstabs, and with nations often sueing for peace rather than be wiped out. And by empire... I could *shock horror*, actually depend on logically sound alliances to hold up for decades and shape the world.
Anyways, this is turning into a mindless ramble
. I for one am glad to see Shogun get another go. I was a huge fan of the original. It had great atmosphere, especially when combined with the fantastic music and videos. And speaking of music...
YouTube - Shogun TW: 7-Miharu Hill