Both of these are the same assignment from the character design class : use a photo pose to create a character based on trees and plant life. I took the class twice, and this was one of the identical assignments (the first design=first time I took the class, second=second time) Which one is more appealing may be arguable to some, but in my mind the second has more appeal to it. I'll explain why below:
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The first one isn't a bad drawing, or even that terrible of a design. But there are multiple reasons why it lacks the appeal that exists in the second one. First of all, I was only minimally conscious of the shapes and lines I was using---I think my major focus was on getting the linework to describe the details and form. Second, the use of space is much better in the second than the first. I think I was afraid to leave any open spaces in the character, because I was trying to describe bark and leaves and I thought I needed detail everywhere to do that.
I think I was also afraid to take some creative license with the photo reference---the proportions and pose are much more interesting in the second one. Turning the head makes a big difference since it's supposed to be a character design and not just an action drawing. That way I could put a little personality and interest into her face.
I think that being a little creative with the style helps the second one also. The first one is so straightforward and everything is presented as literally as possible. This goes into the third point I discussed earlier with appeal---I think with the second one I had a better idea of who my audience was (the teacher and students in the class) and I knew that putting a little style and flow into the lines would appeal to that group.
Looking at both of these drawings, it's clear to me now why I was so frustrated the first time I took the class. There are a lot of good things about the first design---but I think very few of those things were intentional. I can see that something was tickling at the edge of my mind. I had an inkling of what I was trying to accomplish, but I didn't have the tools yet.
Anyway, this is probably a pointless post, but hopefully it might help if there's someone in the same place I was when I was struggling through the character design class for the first time.