I left it open in case this gets others with similar questions about Godot, and thoughts on how to make it a little easier to work with.
I was working on a game that requires a lot of meshes in libraries and grid maps. It seems a bit odd that I have to, every time I create a new one, grab a mesh in the slot, then open the materials slot to put the exact same texture into the materials slot. IDK, maybe this is a stupid idea, but was wondering why we couldn't just duplicate the mesh instance and keep the texture, then add the new mesh we want? As stated, this might just be such a slight issue, but it doesn't seem that way if you're going to be using a hundred or more meshes. Luckily, I'm not using a hundred meshes in a library right now, but that could happen in a larger project.