Dynasty Warriors? Anywhere?

Is that directed at me?

The console versions were. PC versions, well, those were ****ing rare, and previously Steam copies were Asia only.

Really, you want a console if you intend to play the series. Then you have access to Dynasty Warriors, Samurai Warriors, Warriors Orochi, the crossover games like Gundam and One Piece, the Devil Kings / Sengoku Basara series by Capcom, etc.

My all time favorite character is the one you mention Gan Ning. Almost cried when they ruined him with a anchor weapon in one of the later versions since I loved how used his muso mode to run slashing through the battlefield.

I wish but just like many great games like Black and White which is from EA they don't want to sell old games because they aren't major money makers even though it would be easy to still sell the games and have the mod community fix them.

I don't think there is a "new" feature that makes 8 better then 7 however it feels better because:

1. Bigger battlefield, in 8 it's very easy to kill more than 1k troops per battle
2. A few more chars that complement each faction, this makes the later Jin story better since wei, wu and shu will have more unique officers
3. Lu Bu has a storyline!
4. A new mode "ambition mode" which is quite more interesting than "conquest" mode from DW7

Well, sure. Its always based on the same story, so there's only so much variation.

More or less. The game uses the book "romance of the three kingdoms", as such the story is normally the same but told in different ways. DW8 for me is the best because it has a lot of cutscenes for the story.
The main difference between the games are the game modes, number of chars (later games have more) and the way maps are designed.
Lets think a battle like the Hu Lao gate battle, each DW will have that battle but for example in DW8 it combines the battle of shi sui gate and hu lao gate in a single battle, while in DW5 those gates would have been 2 battles with smaller maps.