I agree with the other posters who say quilt the way you like, there is no 'rule' that you have to make a scrappy quilt.
I took an Improv workshop with Cheryl Arkison last year.
http://www.cherylarkison.com/ We did work with scraps, but first we sorted them not by colour, but by volume of colour. We were 4 to a table and shared our scraps. I found that comparing the value of the colours, as opposed to the shade made it much easier to 'let go'.
So instead of worrying about putting green next to pink, I put a dark colour next to a lighter one.
I did discover that most my scraps have a mid range value. I need to add more lights to my stash.
An easy way of determining the value of colours is to take a photo of them and convert it to black and white. If the value is too close, it is hard to differentiate the pieces.