I’d vary the terrain in the center a bit more. Even though the Cracked Oak is scattered pretty well, it doesn’t blend in with the Boardwalk.
Try to keep it around the same shade, too-- the Cracked Oak is really dark compared to the Boardwalk, so something of a middle hue would help. Some lighter stuff, too.
Blastball Court, maybe?
Thankfully, we’ve got a good guide on this, so I don’t have to provide pictures lol
(Technically it’s on paths, but the style matches what I think you’re going for)
Also, tinting Alien Plant props green could be a substitute for the season ticket Grass. I use that trick a bunch.