[Boudica]

I like this sketch a lot. I do think a bit of length from top to bottom would help even out the shape.  This could be achieved with adding the bottom jaw.

In terms of what to do next, tidy up the shape and lines as is, then play with it. Maybe vector it or find a way to edit on different layers so you can try out various additions.

You could turn this into the back of a kind of morbid trading card, or a logo, or a t-shirt design.

Perfectly said.

You've given quite a few options and If the OP takes this under advisement, I believe the result will be a good one. Not that there's anything wrong with the current sketch, but more so It's still In It's Infancy.

A friend of mine used to have an artist motto of "Art is never finished, only abandoned". As a young teen I didn't realise the extent of what that could mean. Now I'm aware that any sketch, no matter how early a stage it is, can be transformed. The hardest part is forcing yourself to put the time and effort in to keep trying things out until you stumble across a result that really works!

[Boudica]

NGL, I don't like it. Looks half assed.

(^clearly not familiar with the concept of a SKETCH)

I like this sketch a lot. I do think a bit of length from top to bottom would help even out the shape.  This could be achieved with adding the bottom jaw.

In terms of what to do next, tidy up the shape and lines as is, then play with it. Maybe vector it or find a way to edit on different layers so you can try out various additions.

You could turn this into the back of a kind of morbid trading card, or a logo, or a t-shirt design.

Fine. Half assed "sketch" whatever

Perhaps I should explain better. A sketch is like the equivalent to doing bullet points for idea before you write a paper/essay for school/university. The bullet points would seem half-arsed as a final product, but we all know it's a starting point from where you build on. A sketch is very similar. It's a way of jotting down an idea or a concept. You can then develop it afterwards. A sketch is rarely the masterpiece itself.