I personally think Radiohead is more talented and I enjoy them more than Coldplay, but I love Coldplay. I was very happy with X & Y but it seems like people would disagree with me. I don't really compare them because it just doesn't work to me. I think Radiohead has something about them that Coldplay will never have in terms of songwriting and just the music.
Maybe you are just sick of Coldplay. Maybe you overdid it a little. I do that all the time. I go through phases with bands constantly. Right now I have been on a Bob Dylan kick for about 4 months now. I can't get enough of him.