Nice tiles, Alistair! Indeed, the tiles you made for Pokémon Acanthite are among the best. I believe that you should saturate them just a small bit, because, from what I see from Kyledove's new saturated style, it looks much better, and it expresses the detail and what they are being used for. I would love to see those trees more vibrant and colorful.
The small trees you originally made for Waudby's Pokémon Odyssey area great as well! I just don't like the area with the stump on it, the shape is strange. Maybe making them a bit larger would look more interesting, and saturating them a bit as well.
Good luck with making more tiles, Alistair! You're improving. ^^