Played this game 90 billion times and I have decide on a challenge not just for this game but any hm game. Basically I'm running my game like it is a super market such as Walmart Hy-Vee and others.
The challenge comes from the keep in stock mindset if I can plant it it sell what ever I have too I have to Maintain my fields at their highest I can afford while also keeping my cost as low as possible. For sunshine island this mean no buying material from Gabon to upgrade my house and farms... I put othe stipulations on for myself. Like be friendly must talk to everyone everyday that I can including harvest sprites. Ill post my rules here sometime from now to share and let anyone else try
I started replaying this game recently too. xD I'm much better at it on the 4th time through, but your approach sounds insane! Hopefully you're having fun with it.
You can only get so far without buying wood from Ganon for expansions.
Early on its perfectly doable, but later on when you need massive amounts of wood for upgrades, the game simply doesn't offer enough as a natural spawn for you to upgrade your buildings.