Using the Pro Tools Tempo Ruler gives you a lot of creative ways to visually change your session tempo's. It gives you the ability to use multiple different tools and methods to change the tempo. In many ways, using the tempo ruler is similar to writing in track automation.
The Pro Tools 12.5 Dashboard has changed with the addition of Projects. This is related to the new online collaboration feature. The settings for Projects and Sessions are slightly different and default Pro Tools settings can be a bit problematic if you are not aware.