When it comes to the anime, they tried at least. They were able to do Arc's true story with only a few major problems that only an annoying fanboy would complain abou- oh wait...
Lack of points
Nero wasn't bad-ass at all
No chair.
Sacchin actually lived, seriously what the hell is that.
Kohaku wasn't faking being happy, and was just a stupid side character... which is absolutly unforgivable. :'(
Apart from some other backsotry parts they did follow Arc's story nicely.
However, that made all fans of other characters a little annoyed, same thing happened with FSN (actually my main beef with that anime is CG dragon and how they tricked everyone in the 2nd opening with UBW)
Overall though the anime has some very nice artwork and a good sound track. Game is still loads better though.