I think Samanosuke Akechi of Onimusha fame would be a great pick. Not only was Onimusha synonymous of the Playstation 2 early on being its first million seller and at a time being a primary mascot of Capcom (its #5 among Capcom's most lucrative franchises though that might've changed given its absence) Samanosuke is a pretty interesting character with a wide variety of abilities. Not only can use a bow for distance attacks but hopefully they'd work his eight elemental weapons into the game. He'd be the perfect rival character for Kratos and then throw in his Onimusha form! They'd be crazy not to consider him at least
My character wishlist would go something like this, I'll try not to have characters that overlap/play alike
1. Dante
2. Ryu Hayabusa
3. Samanosuke
4. Ryu SF
5. Rau (Mark of Kri)
Rau and Tati would be effing awesome.