Assembled Nurgle Blight Drone

I put together one of these last night and added a bunch of guitar cables.  I've never worked with those before but it was pretty easy and I like the look.  I have one more of these to clean up and mount as well.  Until I get IA Masterclass II I'm not sure I'm brave enough to paint them though.  I really don't want to mess them up and the rust and stuff scares me. 

I still haven't come up with a 'list' to aim for as my builds are always fluid each game anyway, but this is what I have so far and also what I'd like to grab

Forge World Nurgle Daemon Prince - Not sure how to play him - Mark of Nurgle and Rot? Otherwise why does he have that giant gun!

Forgeworld Nurgle Terminators - I need to either buy the kit or find someone to trade for my Tzeentch ones.

Forgeworld Plaguemarines
GW Plaguemarines

Fast Attack:
Dread claw
Blight Drone
Blight Drone

Plague Hulk of Nurgle

So the question for the audience:
Should I go with a set of FW and GW plague marines so that they're different or just get 2x forgeworld ones which in my mind look way cooler and really give you more flexibility since I'd have 20 instead of 17.