And hear hear, Khorin, like a majority in the WB community I'm a TW fanboy too, this series used to be my main games until I stumbled on Mount&Blade back in 2005, though I'm a bit disappointed at where CA seem to be heading.
I still think the first Medieval is the best in the series (especially the Viking Invasion expansion) and the first Shogun was awesome too (especially the Mongol Invasion expansion), though I'll readily admit RTW is superior with mods, and the most sleek engine in the series so far (and Barbarian Invasion was really good). Medieval (1) just had a more in-depth campaign map with more RPG, events and dynasty politics a la Crusader Kings II, and the series were more focused on historical accuracy back then, which has gone the wrong direction after RTW and Sega becoming increasingly Hollywood, pop-history inspired, 'Gladiator' Roman(philia) period (naked barbarians throwing heads at lorica segmenta wearing, pilum-machine-gun-shooting romans etc), the US as a World-scene player in ETW and the new Tom Cruise samurai BS as cases in point. The current generation of mods are mostly for MedievalII which has never been a really good engine, despite the obvious success of mods like Broken Crescent, The Last Kingdom, Third Age etc. Let's hope the EBII team can make up for its shortcomings.
I have admittedly not played Total War games much since M&B became an option (some NTW and ETW and mods like EB and The Last Kingdom), for action I go on WB servers, for strategy I go to Europa Universalis or Crusader Kings, and I'm frankly disappointed over the arcade direction the official series has taken (and utterly retarded AI in all the games, even with Darth mod, perhaps with the exception of increased ambushes in Shogun II, over-expensive on-release DLCs, completely buggy and desynchronized multiplayer battles in all the recent installments, general lack of community support from the Creative Assembly and non-working multiplayer campaigns despite announcements to the contrary).
Except for that the new games are quite impressive visually (nice and largely correct uniforms especially in Nappytw) and audibly and I think the transition to the gunpowder age and the sea battle inclusions have worked pretty well for CA (though sea battles quickly get boring in MP and artillery-spam could be considered unbalanced). The only really nice new campaign feature I can think of is army attrition, though this was 'inspired' by the modding community. And yes, some long-waited improvements in diplomacy and more 'full-stack' battles than the consistent stream of skirmishes the older installments suffered from.