Changing the look of the external render

My house is rendered outside with dark grey chippings. It looks kinda dark and depressing.

Would it be ok if I brushed off all the chippings and painted it white?

Also I noticed there is a crack running up vertical in part of the render, it is about 1mm wide. Should I use some sort of dremmel thin grinding tip to gouge the crack bigger and then fill it in? What do I fill it with?

 

itll look bad.
exterior filler, or fill it with paint as you go.