Haha, you're welcome. Feel free to use the tiles as I've posted them, I don't care. Even if the game profits. They're just modified versions of yours, anyway. Seems like yer getting the hang of it.
I'm gonna go ahead and move onto those pesky tree tiles now. You told me in a PM that you're having arbor-related nightmares, and that you hear the voices of trees in your head, taunting you when you venture outside. Hopefully this next bit will assist in that. Or it might just make it worse.
This post isn't comprehensive. It only covers tiling theory, pertaining to making a solid tiling texture depicting repeating objects that span multiple tiles. How does that work? WCII's trees are the prime example here. The rock tiles are good too, but screw them, we're doin' trees.
The following animation states this, but for clarity I'll say it now - the basic principle at hand here, is that you can create a square tiling texture with obviously repeated objects (not just a little detaily pattern) simply by spacing them apart a distance equal to your grid's X and Y dimensions.
(I hope the framing timing isn't
too annoying; tried my bestest)

The above GIF is large, including seemingly unnecessary parts of the canvas, because I wanted to include
some of my working area, for general consumption.
Especially notice the Master Tiles, sitting in the pink cloud. Minus some "special tiles", that are only revealed in-game as the tree tiles are chopped away by the worker units, the included Master Tiles are all you need to replicate any configuration of trees - works the same as most other tile-sets in WCII.
Next up: Tree Transitions. I'll cover it later, but here are some helpful animations 'till then.
Successive screenshots, recording the effects of a worker unit chopping out one tree tile at a time. Notice how the adjacent tiles react each time.
This is the game engine doing this, not me. Yes, only one tile is being removed at a time, though it appears that two or more are removed a few times.
If you scrutinize what's going on, you'll probably agree this is simply the way it has to work.
Can you find the "special tiles", mentioned earler?

Same winter grove as above, disambiguated, before any chopping occurred.
Large area of tree tiles disambiguated with simplified tiles.(all credit to Blizzard, I'm just intrusively deconstructing what
they created)