As part of my pre-production design workflow, I like to approach in a particular way, before I get too stuck on one design, I begin by exploring various possibilities, for this matter I use software such as Alchemy, this software allows me to create fairly quick abstract shapes, which then I interpret my own way.
With this shapes I then take to Photoshop, and try to visualize characters. while normally you develop the character and then check the silhouette to see if the design works, This method allows me to work from the silhouette and de-construct what I can possibly fit inside. This approach is very beneficial in many ways, firslty allows me to explore any designs without restrictions, it helps me see form and understand it within the shape, and quickly brainstorm possible designs for a certain character, ohh and it is very fun!!
With this said here is what I came up with. One the Left you can see the final sketch, based on the shape on the right. (although rendered this sketches took me maximum 30 mins to brainstorm.)
From the designs I came up with, some of them, for instance 1, 3 and 6 are closer to what I want to achieve with Olivier, though all of the designs have something I either like or will add onto the final design of Olivier.