I went ahead and assembled a full squad of 10 of these guys, which takes two of the metamorph boxes. The Metamorph Leader is the guy in the middle with four arms holding a skull and spinal column. I've been trying to get him to put it down for a while, but he keeps carting it around like a security blanket.
Here's five including the leader in a little more detail. The only concession I've made to the game mechanics at this point is that I've given them all hand flamers rather than the standard autopistols. Autopisols give you more range, but you only get one shot and with a 4+ BS, half of those are going to miss. The hand flamers give you a lot more potential shots (Pistol D6 rather than Pistol 1), and they're all automatically going to hit. This is primarily a melee unit anyway, so may as well give them a ranged weapon that requires the unit get "up close and personal" with the enemy.
I've tried to go with a variety of icon/banner colors for my units. These guys obviously drew the color blue which carries through the banner and any robes or partial robes the unit is wearing. The rest of the paint scheme is very similar to what I did with my Acolyte Hybrids last year. Ultimately my plan is to go ahead and work up another group of Acolyte hybrids that I could run either as a second unit of 10 or combine with the existing group and run as a mob of 20.