Haha, I feel so weird just now, I usually encourage wordy and pick-apart-y critique, but I feel a pressing need to just give praise for you and your tremendous improvement, especially on the grass tile - it started out as something quite hideous (but with a clear idea and thus potential) and is now something very nice to rest the eyes upon!
Same with the dirt tile - I'll be a bit more constructive here - I can think that making things 'not tile' can be too much of an undertaking sometimes. Tiles tile, that's their nature. Making the tiling into a smooth and even shape is priority, because then it'll be even easier to add break-up tiles that make things look more natural. I think you're doing great with this. So keep it up!