Cool, a fellow Monkey Island fan. ^^ Sorry, I haven't commented here like forever since some time.
I like the contrast you created by drawing the fore and back ground in different styles. Guybrush and especially the ape (Mr. Nilson XD) are on the realistic side of cartoon design, while the sky reminds me of the night levels in Psychonauts (it's the clouds, I swear).
The pins on the seams (do I refer to it correctly?) are a nice touch as they give the feeling of a different clothing sense and make out of a jacket this individual, pre-18th century look. Maybe the colours are distracting me, but I think Guybrush's hands look too small.