Yo! Awesome!
The thing with the assets is that until now we always only had a vague idea how to structure the data packs. And what formats the graphics should be in. But we're getting a clearer picture now. If you like, you can submit the pull request against the data-repo just now, so we can merge it sooner or later, but at least it doesn't get lost. If you produce more textures, you can add them to the pull you already sent then.

@KevDoy The grass already looks pretty good :)

You can make a PR right now because if there is something to discuss, we can solve it once and you don't have to make a bunch of changes to all textures.

@TheJJ oh good to know. I noticed AOE2:HD uses PNG files for these tiles which is how I easily swapped them to test.