The first thing I noticed about this gobbo is that on the sheild hand, the brightest green is in the recesses between the fingerswhere the shadows should be, this jumped out at me straight away and needs fixing, though is ded simple to put right with dark green or black ink and a steady hand.
The face is looking very nice, and I like your skintones and contrast. The teeth could do with some more browning nearer the gums, and fading out towards the tips.
Also, the arms need highlighting to a similar level to the face. May be the picture but are way too dark as it stands.
The metals are great, this is one area you have definatley improved on, the greenish rust on the sheild is a nice touch well done and suits the character of the goblins.
If this was my mini, I would be tempted not to include ANY freehand on the cloak- not only is it not in the goblins character to be elaborate, there are many creases making it difficult, and I would work on getting the basics spot on before showing off on areas.
If you are certain that you want to include freehand on the cloak I was thinking of a grinning faced crescent moon first off, but the paint scheme you chose doesn\'t really suit the night goblin imagery. I think a row or two of black and white checks at the bottom rim of the cape would work better with dirt painted over this to show wear and tear.
A good start, keep it coming!