*applause*
They look awesome! You can tell, because everyone is giving you advice on basing and not painting

There is one more thing you may want to consider. If you look at my
Mega Armored Warboss Toegnasher, all I did was cut up sprue and odd bits (I HATE topknots!) with an exacto knife. Put some superglue on the base, spread it out with a toothpick. Sprinkle on your cut up plastic, then base it black and drybrush grey. If you want to add a bit of something fun and dynamic, try adding weapons or helmets you aren't going to use and paint it in the colors of your favorite enemy or even alternate army...like your Eldar.
I hope that helps!