I have to admit, the Ravens' mascot logo is very cool looking. That is one mean bird, isn't it? Put that raven up against a cardinal, and I think we all know who would win, regardless of who might win on the actual field. The top right design uses a matte finish, which is very hip and modern these days, but it is a little too similar to the usual helmet.
The two bottom examples are very drastic design choices that forego the mascot logo entirely. The bottom right logo simply uses the Baltimore B, though I don't think that is going to become iconic anytime soon. The bottom left isn't so bad, using an abstract feather design, but I think it would lead most people to miss the old logo. That Raven logo is just too good.