Don't worry about the discoloration - it's a user, now. Over time, with continued use on a variety stuff, the patina will even out....you may get some colors running through it. Or you could force more of a patina, now, to change the look.
If your goal is to get it gone (which is how it sounds) - before you do anything else, you need to accept that there may always be some residual discoloration there. Clean the blade with some alcohol (isopropyl or denatured - save the good stuff for your internals), then use one of the products mentioned (I use simi-chrome or metal-glo). If it doesn't clean up well enough with a cloth, try repeating the process with some wadded up foil - it won't scuff the blade, but it gives some oomph to the scrubbing