Purple with turquoise would be for the lords, Mistmor and Flaithmor, and then just turquoise for the heroes, Flaith and Finmor. I think I'll also add some turquoise cloaks and bits to elite troops like the marlwyrm riders, fianna fimm and so on. With the army having a very earthy palette, it needs some of these tones, along with the leystones and shields to lift the models a little. The half dead in particular needed some contrasting focal points to make them pop, the shields and glowing eyes being the device to do just that.
As to characters, I have some decisions to make. I have a converted battle standard Flaithmor in the works, a shearl wizard primed, as well as the finished meargh. Next up I think a Flaith using Jervis Johnson's original fimir, as he kind of has to be in the army somewhere. I want to convert a human scale dirach, which I'm using this model as the basis for. Take off the head and give him a horned dirach hooded head, change the staff some and he should look groovy.
I want to include some of the larger dirach too so I had an idea to use one as Throg. It seems appropriate for a dirach to be leading a unit of fenbeasts (trolls), and gives me an excuse to paint up the Nick Bibby dirach with the staff.
I do want to add the other dirach and nobles in too, at some point. The nobles, along with the Forge World fimir, are destined for a unit of eight to act as ogres, or actual fimir from monstrous arcana. The second large dirach might end up on a converted war shrine.
So, the characters should be pretty identifiable amongst the cyclopean horde. I guess I could always stick them on a big rock too, if all else fails...