So much this. They had something amazing going starting with Shogun and then completely blew me away with the first Rome. Medieval 2 is where the franchised peaked and it was amazing. Lots of unit/nation diversity, pretty fun campaign map, etc.
It all went to shit with the release of Empire. Homogenized units, nations that essentially just amounted to "choose your flag color", and naval warfare that was slower than watching old people fuck. I thought they might have turned the corner a bit when I saw the new battle system with Shogun 2 (seriously, the way units clash/fight in that game is about as historically accurate as you're going to get to "real" battles in a video game), but they had to fuck it up by adding a bunch of extraneous shit like general leveling, the town building/branches/ etc. Then, they followed it up with a shittastic release in Rome 2, which had the same extraneous bullshit, plus bugs galore. A friend of mine says they fixed it with the expansion (which, they usually seem to do - the original release seems almost like their beta at this point), but by that point, most people couldn't care less. It has been this way since Empire and I haven't touched a release of theirs on "release day" since. Shogun 2 and Rome 2 were both "wait and see" with me. Shogun 2 I ended up getting on a winter sale, so it only cost me 15$, but I still have yet to purchase Rome 2. I'll be taking the same approach with their Warhammer game, but I'm betting it'll also have its fair share of issues.