Wow! That's some serious EXIF data! I can't say that I blame you for wanting to get rid of some of it.
Other than doing it manually, or stripping it out completely in a Save As process (which I don't think you want to do), I honestly don't know what to suggest. I even looked at the ZoomBrowser software to see if you can tweak the data there.
Have you asked about this in a forum at Flickr? I'd give it a try.
http://www.flickr.com/forums/