Replacing them is a little extreme for just changing the colour of one bit of padding. I'm considering the inks from a permanent marker, and if they don't work, I'll steal some of mummy's dye. I'm sure she has some red somewhere!
Stapling some material over them may not be as crazy as it sounds actually, (1) extra padding and (2) my own design work (perhaps speak to a friend and get a embroidered logo... *brain clicks into first gear*).
As for me and paints? I'm a perfectionist, if it's not done perfectly, it gets done again from scratch!
As for the dodgy knees? Join the club, I have tibal-osteoperosis or something with a fancy name like that (basically too much cartilage between my knees making them painful occasionally). I have to know all the 'medical mumbo jumbo' for my degree. Today I was tested on 20 bones from the body, which was great fun, got a 40 bone test coming up on my birthday (next Friday).
Anyway, I should get some work done so I can spend some time finishing my spring armour tomorrow and not feel like I've got no work for university done!