Chaye,
I have posted some of the places to visit in my previous post for Albany. You may like to check it out.
For Denmark, you can visit the following:-
1) Green Pools
2) Elephant Rocks
3) Bartholomews Meadery for Honey Wine
4) Toffee Factory
5) Denmark Dinosaur World
6) Denmark Maze
On your way to Perth City from MR, maybe you would like to visit Abingdon Miniature Village in Mandurah.
For Perth City, you can visit London Court, Lake Monger, Swan Bell Tower, Kings Park, etc...