Maybe one is still existing or done, but it must be somewhere sunken and I won't dig up after long search ....
My whishlist for Shogun 2 is:
1.) Full modding possibilities
2. The old reinforcement system of RTW and Med2TW or even better, but not again that crap in ETW/ NTW!
3.) Smart AI (CAI and BAI)
4.) Hotseat Modus
5.) Huge diplomacy menue with many options and smart options to choose!
6.) Nice artwork at units
7.) A good trading and merchant system, including taxing etc.
8.) A big campaign map of Japan minimum, many provinces too!
9.) Not only few MP battle maps!
10.) A map editor for battle maps as it was given with RTW
11.) High game depth which is not only superficial
12.) Some historical events implemented, not only a message
13.) Better setting of difficult degree's that please fans and casuals, no compromise only!
14.) No science fiction stuff or ahistorcal nonsense please!
15.) A better Rebellion system with more background and deeper impact
(not only angry population, some useless (ETW) or overpowered (NTW) Rebells and thats it!)
16.) Siege battles must be splitted. If a fortress, than really a fortress. if a town, than please a really town!
17.) Shore and offshore naval battles
18.) epic general speeches + epic sound and music
19.) good campaign Addons, that are not only a single mini campaign, they should be implemented to the grand campaign (for example later Korea too or so).
20.) please not a remake of the melee acting of RTW and Med2, a new and epic one during battles!