Well, then you're just screwing over yourself. Here's why.
1. Too big? Its too small if anything, and you can easily change the size to whatever you would like...
2. Why? You can essentially be creating yourself all the same, the only difference being you wont have to go through the tedious process of selecting all the scenery and rides etc.
There's really no reason not to at least use the PT2 bench as a base for the scenario, it contains the optimal arrangement of scenery with the exception of a few of the objects at most.