Bordo,
As you can probably tell, it doesn't matter too much what thickness you make the blade; someone will think its great, and someone else won't, whatever you choose, so go with what you have and see how it works for you

. That's what matters most.
On the handle, I think you have made it too skinny / not deep enough, and particularly not enough to balance the depth of blade. Could be wrong and it might just be the photo, but it looks like the handle up at the front end is less than 1" deep while the blade is pushing 2". That front part of the handle is what you are going to be hanging on to to resist blade torsion whether you are chopping or just carving feather sticks. Its going to be hard to make it comfortable for medium to large hands with less than 1" depth. You don't really need finger clearance space between blade edge and handle like you do on a kitchen knife, just tip the blade forward and cut a little more on the belly when working on a board.
At the butt end, if it was me, I would have kept that convex area since they can work well to improve grip and resist the knife trying to leave your hand when chopping or snap cutting. A knife like you have drawn is great for de-limbing saplings with a snap cut.
I hope you don't mind me posting photos to illustrate what I mean...I will take them off if you want.
If you want to chop, you can drop your hand back and that necked area can be great for giving a secure grip.
Best of luck!
Chris