I really liked the entrance area; simple and open! I checked out the cafe area next, I thought the placement of the tables and chairs was on point. Have you thought about possibly adding food/drink items on the tables? (Also, I love that the extra characters are named after what their houses represent! It adds a little flavor to the map.)
Honestly, I loved the park area with the checkerboard pattern, but the tricycle got in my way a few times. The playground area is so cute. I never bothered with the tires but you used them to excellent effect. It really feels like a playground I might have played in when I was younger! I think what you've done here is fantastic; until they add more rides, I don't know what else you could put. Maybe a little shooting range? Have a stall, some balloons positioned behind it, or a sign with a target design on it. You could also move the little wooden play thing (I forget the name), over to the snack area so kids could watch it while they eat snacks.
Overall, I enjoyed your island! There was no lag and other than the tricycle incident, no real obstruction to wandering around.