Having worked on a few animated projects during the last three years or so taught me a very valuable lesson: there is no such thing as "ripping someone off" as far as my perception goes; when you work on an animated project that requires you to match a style given by the animator director, you have to copy all of it or else they will fire it up your ass and you end up being kicked out of the project for being unreliable. Down to even copying the style of linework and mentored to avoid mistakes by COPYING my animation mentor/director and analyzing how he does it, I have managed to solve a lot of things on my own style and I am still proudly applying all the "acquired" knowledge on my current work.
"Style rip-off" so far appears to be solely based, to me, on pure internet/deviantart/conceptart/whateverart bullshit where a lot of people constantly try to stand on top of the other by being "lolriginal". If you want to improve, go around and analyze other artists, COPY them to your heart's desire, redraw and learn what makes their stuff so appealing to your eyes, even tracing can help you big time (I know of animation assistants who are -forced- to trace every drawing given by the animator, years later they become senior animators themselves or comic artists with an amazing style)
Found someone copying your style? be proud you are being exemplary to them instead of cascading menstruation upon them for even attempting to do so*. Think your style fails? copy other people, even ask them for help.
* - I don't mean plagiarism of ideas, I'm telling you about the phisical or visual look of whatever you do.