Went with a plain-ish base, then for paints, a simple, holy-ish feeling white and gold scheme using some combos I like a lot
grey seer shaded with thinned washes twice, reikland then drakenhoff, for the white
then runelord brass shaded with reikland for the gold
I think I've got the big parts in place for this
swapped the normal sisters faceplate for one from mechanicum tech thralls, used a secutarii arm and shield, and added an electro-priests collar-cog to the power pack
Now I just need to figure out a base