Hello! well.. You asked for it 
here you go..
First of all I think the presentation is very nice.
I don't mind the idea of the design itself. I would Maybe suggest to play around with sizes\colours a lot more when you design something. For example, You've got pretty big coat, pretty big legs, big hair - try to breakdown the design into Big, Medium and Small (like big coat, medium hair, small legs, or big coat, medium legs, small hair) better explanation in Sinix's video
Also to checking readability of the silhouette is a good thing and helpfull thing.
Check out Marco Bucci characted design series
- it might be a different style But i think there are plenty of principals that could be (hopefully) usefull.
But there are small things, however I like your design, I think you did a very good job!
moving on...
I would like to point out that you could improve your anatomy. I say that because as to a viewer I don't quiet get if she is a bit chubby or very muscular. I'd assume she is meant to be muscular only because of the arm, however it is not clear how muscular her legs are. If you wanna show her very chunky then I could suggest you to define muscle forms better on the legs and the abs.
Also overall running pose looks a bit strange because of the right leg (the knee and the leg itself wouldn't be pointing to much to the opposite side.
As for the render part and the linework I think it is a nice style, I like how some areas of the line are thinner and some are thicker!
Maybe adding broader hue to the skin colour and the jacket could help with the visual interest quiet a bit.
and one more thing, (probably personal taste if anything..)
but I feel like the jacket is the most important part so maybe making it orange instead would be more cool than brown, because brown is not a very popular colour it doesn't excite the eye too much.. but that's just nitpicking.
But ye overall very nice presentation, very cool idea, the linework is great!
I hope that I wasn't too harsh but most of all I hope it helps 
