*In response to long post by SSp I'm not going to bother quoting*
(ow long posts with few line-breaks) Metal Sonic looks like Gigan, a robot version of Godzilla... I only remember him from promotional art though... The face looks the same, but its only because the back spikes characteristic of Metal Sonic aren't shown that it looks so much more like him.
As for recognizable, the only way I recognized Knuckles was the fact that he was missing... and I originally thought that Tails guy was a fancharacter. I like the pic of Metal Sonic and Eggman, but as for the detachable limbs and such... I'm not personally wild about it. (I prefer fantasy for Sonic)
Amy really looks human mainly because her eyes and that her design isn't very animal-ish anyways... I personally like Amy more than Rosie... even though the hammer is somewhat impractical.
And being that the Tails that has been my favorite character since I first played it, I am slightly bothered by his SA+ version (tech expert??? It seemed cool at first, but he's just lost that lovability). Even then he's still SUPPOSED to be (if you mute the speakers) a cute little fox.
It is constructive criticism... not a suggestion on how to *fix* your art as there is no such thing with art. Concepts can be improved, but cannot be fixed. Although I must admit your post has confused me with its incoherence, it seems that you are asking for criticism to *fix* your art and at the same time passing it off as 'just my opinion'... My opinions as stated were that Sonic and co. should be caricatures and that Tails should look cute... but keep in mind that I did point out that Tails and Knuckles are unrecognizable, Sonic is too stocky, and Amy is too human. (she doesn't have hedgehog eyes) While yes that may be in my opinion, it was intended to be advice and careful criticism on your art from my point of view, which, being myself, I kinda have to look through.