Currently, 10 is the maximum number of stations you can see on the graph. You can slide over to view the other stations. To view them all on a single page, please see below for the workaround.
However there is another way, a bit more convoluted but does the job. You can achieve this by using Custom Reports.
1. Go to Reports & Alerts -> Custom Reports
2. Click on Add
3. Fill out the Title to your needs.
4. Choose the type of Display you want.
5. For Shown, select "on average"
6. For Group, select "by station"
7. Fill out the Monitors and Monitor Groups to suit your needs.
8. Click Save.
You will end up with something like the below screenshot, listing all the stations. In this example, Performance was the type of Display chosen and all stations were selected for the Monitor.