I forgot to amend the latest map with Maelicent's change in position, but since you're asking about E19 maybe my forgetting is a good thing. The tree in E19 is actually a young tree more than it is a sapling (but I'm fine with continuing to use sapling in the IC as descriptive text). Sharing its square isn't feasible, but I do understand that Maelicent's going for cover and will provide it to him if he stands in E20, which is where he is now. He'll be able to hide and take cover and snipe, getting to do all the things you've declared for him. Another square that may appeal might be D19.
Looking at the map, I think the square he's in right now (E20) is actually a pretty good one. I'll gladly amend the map to have him move elsewhere if you'd rather.