Looks a bit untidy and flat so far. I think the fewer colours to take away the focus from the pink and purple, the better. Avoid metallic gold, it doesn't go well with pink and the paint itself is awfully difficult to work with.
I would suggest that you start by basecoating the whole model in pink. That way you don't have to be terribly neat with successive coats and you won't have any gray patches if you miss a spot.
Wash the whole model purple, this will bring out all the armour paneling and other texture. Then just paint solid purple in the right places, highlight it, pick out a few details and you're done.
These guys were painted as above, using P3 Carnal Pink, Vallejo Purple and Vallejo Glaze Medium (combined with the Purple to make a wash).
Hope that helps.