While 4 is usually the favourite from what I've seen, for me the clear peak of the musou formula is in DW5 and its expansions. Even further tweaks to gameplay were made that saw the removal of the lock-on effect during combos (the best change) giving you more fluidity in your combos which were extended to like 9 hits or so. This provides more options and a more dynamic gameplay experience which, lets face it, does become a little mundane even for hack and slash enjoyers. The movesets are so tight and feel so unique to each of the characters. The way they're executed is reflected really appropriately for the character's personalities which all feel very fully realised in 5 as well as their look and design. In spite of these gameplay elevations it is really the story that takes centre stage in 5 for me. While it clearly follows the same narrative throughout the franchise over and over again, the presentation of the storyline feels fully realised here.
There are some gimmicks like the god-mode powerup thingy I don't even know what its called, and the joint-musou attack with your bodyguard, that do make this game substantially easier just across the board. Though, I don't mind it as for me bearing witness to this game's iteration of the characters and story always made this Dynasty Warriors the real treat for me.
To discuss some flaws, mounted combat still sucks and going into the arrow shooting mode feels as trivial and pointless as usual. Also the artstyle in this game is great albeit very dusty(?) Honestly if you've played the game before you'll know what I mean. It just looks very dusty all the time lolllll. This will always be my game though <3