EDIT: I removed several parts of this post, so as to be asking for critique on only one item. Hopefully it's better to modify this post, rather than start a new post.

Hi there!

I've been lurking for quite awhile - you guys are great! Skilled, helpful, and kind.

So, I'm only a dabbling student of art, but I've been trying to put together some assets with which to start working on a couple of game projects. I'll include everything here, so as not to triple-post, but hopefully someone can let me know if this would do better being split up.

I'm asking for help with some game assets, specifically a large tree. The game is drawn at 640x400, intended to be doubled/tripled to fit the resolution of a modern screen (i.e. 1920x1080 or 1200, something like that)
The Tree:

Some simple context:

Tiles in simple mockup:



My main concern right now is the trunk, or wood of the tree. I think I've gotten the palette fairly close, but the patterns/clusters of the detail have been giving me trouble. Too busy, perhaps? Also, I've never tried AA, and since this is meant to be scaled up 3x, I'm not sure if the jagginess is too harsh - I do like a a few rough edges, but I haven't really refined how to incorporate that successfully. Also, the tree looks flat right now - I'm hoping to incorporate a lighting system similar to something like sprite lamp to give it more of a 3D shape. I'm not sure about the dithering to indicate light foliage, I'd be happy to hear suggestions on how to improve it. Of course, all other comments on the other parts are very welcome as well.

Thanks for reading this far! Apologies for the wall of text! I'm happy to answer any questions as well.