Study for painting: The Visitor

Here's a study I've been working on. It's not quite finished and photographing it has revealed a few areas that need improving. I've got the canvas ready but shall I go for oils or acrylic paints?.. the stinky, headache-inducing, slow-drying oils or the not stinky, quick but a bit crap acrylics... decisions, decisions!

Study for The Visitor 
Gouache on black paper 
Jane Pearrett 2016