They were all made to look like the armed one is treatening the other ones, which helps blend the two different version together nicely.
As you can see, the base is both swamp-like and bloody, which helps add to the nurgle look imho.
After painting the nurgling, i wasnt quite sure about the yellow look they had, but after puting them on the bases, i think it works nicely ; they definately pop more than if they were green or brown.
The blood is a nice touch imho.
I wanted to do some bloody strings on them (kinda like my Dark Eldar), but after seeing how fragile they were, i decided against it. Blood adding to the murky water is much better looking imho anyway.
I seriously considered painting their face white like clown, but figured at their size, it wasn't the best idea.
On some base, i only put 3 nurgling (to add some variety), but added some small piece to make up for it. I did end up with 2 extra Nurglings, but i guess i'll just have to get more eventually.
And some side shot ;