1) What is your thoughts and feelings about Nero being made specifically for the Devil Bringer
I don't feel Nero was just a vehicle for a new mechanic. Dante, in many ways, had reached his developmental peak, both in terms of character and gameplay. Nero provided a way in which to continue expanding the mythology while also crafting a new play style.
2) Should Dante of just had a Devil Arm's that gave him the Devil Bringer powers
No. I agree that it doesn't "feel" like Dante.
3) Do you think Dino pulls it off better then Nero?
Like someone else mentioned, the Devil Bringer, in a lot of ways, defines Nero's style. He was built around it and Exceed. DmC Dante is not wholly designed around the grapple function, though he does have the advantage of moving towards and away from any enemy, whereas Nero was limited to one or the other depending on the opponent.
4)If so, does that invalidate Nero's existence in the first place?
No. Like I said, Nero had a bigger purpose beyond just being a test drive for new mechanics. Whether or not his potential will be realized in future hypothetical DMC games remains to be seen.
~@_@~ Why are you people so hung up on what's canon or not? - freakazaa