I think you should definitely leave them alone. A few dozen scratches on a mirror is purely a cosmetic problem. In fact a few hundred thousand scratches on a mirror is purely a cosmetic problem :-)
I remember when I made a 50mm finder once using parts from a cheap binocular. The inner lens of the Kellner eyepiece was made of plastic, but I was too careless or ignorant to notice this so I cleaned it by forcefully rubbing it with a paper tissue. It became so badly scratched that I was certain I wouldn't be able to use it, but surprisinly there was no apparent change in image quality. Since then I haven't paid much attention to local defects which are not near the focal plane...dust, scratches and such are in my opinion insignificant compared to things that really do matter, i.e. optical and mechanical quality of an instrument. Of course it's nice to have a shining mirror which appears flawless when examined in bright light, but who's going to look at it in the dark..
Jaakko Oksa