Dear Khun เบน,
You can also get alot of inspiration from NOCH Ready-Made Layouts which might help you with your planning. The good thing about them is that they already have calculated the % incline which the locomotives can do and is a perfect fit for Tracks such as Fleischmann, Maerklin, Piko, Tillig etc ...
Go to this link to see them all:
or key in "Noch Fertiggelaende" in the Search Field na krub.
Hope I was able to help you a little bit.
Your Zug Haus Team