Fast color fill

Another way using free Extension

you would have to create  individual shapes with ShapeBuilder tool

Color Tweaker By Creatide

For  fills/ stroke / text 

Select objects, even hundreds, making sure they already have any fill etc

Hit Random Colors and it assigns a  unique, but  purely random colour ( ie not from swatches) to each object

https://exchange.adobe.com/addons/products/3288#.WfDSYm5rzb0

''Description

Color Tweaker is super easy tool for tweaking your artwork colors in Adobe Illustrator. You can easily change your colors from dark to light or just tweak the chosen color channel. And with "Random Colors" you will find fancy and great ideas for your color schemes! Color Tweaker deals colors in RGB values, but it also works in CMYK mode by converting colors through RGB values.''

First use live paint or the shapebuilder too to generate them as single objects.

Then use a script. See here fpr the details and download http://vectorboom.com/load/freebies/freescripts/randomswatchesfill/22-1-0-167