I built Lake Greenwood with a very simple start, I didn't plan anything. It was the alpha 3 release and all I wanted to do was check out the fairy tale sets. So the only thing I had on my mind was "Build a simple entrance with a few fairytale buildings and a couple of rides",
Once I had more money I thought it would be fun to make a junior coaster, continuing the fairytale theme and sprinkling in some more flat rides in between,
Then I branched off again with new ideas,
Until it became what it is today,
My current park is built the same way. I had the original idea of making a lodge entrance in an alpine park,
I then started branching out with every new idea,
Here it is currently,
The overall point is, or at least how I like to play is don't over think and over plan. Start yourself off with a simple idea for an entrance plaza and keep branching out with every new idea you have. Your parks will grow more organically and you won't feel overwhelmed with too many ideas when you're just focusing on one new branch at a time. I find this way more enjoyable as even with just an entrance, a few flat rides and 1 coaster, the park feels "complete" so I expand with a new idea, new themed areas and it's like I'm developing a real park over time.
I hope my method can help [up]