To me, it offers another view of who Dante is - a bit of history and also emphasizes on how he feels and acts as a half-breed. A bit like supplements, like the manga. The game series stresses on his styles, history, physical abilities and strength, whereas supplements like anime helps refining the emotional aspects of Dante... Sorry if I am not making myself clear: commenting on ambiguous stuff (i.e. feelings) are tough
It differs from the game in terms of what it's emphasizing so I didn't really compare it with the games. Reuben Langdon did a fantastic job in bringing out Dante's spirit as in the games, that's why I am so inclined to get the rest of the episodes in Eng. dub as well.