I have had my hair highlighted for about 3 years now (about 3 x a year), usually with a couple of different shades. The more it is done, the more of my natural hair ends up highlighted, so it is getting ever lighter. The obvious thing to do seems to be to dye all of it closer to my natural shade and start again, but 1) my natural colour is the most non-descript sludgy mousy colour and 2) I don't want a hard roots line as I'm not one for keeping in top of it regularly. So what do I do? If I go for darker highlights instead I'll end up with five different colours in my hair. I assume this is a common thing for anyone who gets highlights, but I've never got to this point before so advice appreciated thanks!