Yeah, more paint is needed to make an honest assessment. I will say however that I am uncertain how good grey armour will look with brown cloth on the FW's. On the A'un it is alright but warriors of any kind tend to look more straightforward. Be interesting to see how it all turns out.
One suggestion I have for you is regarding the Piranah. Just for the hell of it, I modified the gun drones to have burst cannons on the model (still just gun drones in game of course) and it turned out super cool looking. I would highly suggest it to you. Matter of fact, check out the pic:
The drones can detach as well and look awesome flying around with this big ass gun strapped underneath them. I have gotten more comments and compliments on those drones than anything else in the army actually.