So i just setup a panel on the top and on the left side. Left side is set to only show favorites, and I have no favorites pinned to the top bar.
One thing I noticed is that since in order to add an app to the favorites of a panel, it must be open on that panel. Since my left panel is set to only show favorites, I have to change that setting every time I want to add a favorite to it.
My suggestion would be to allow right clicking apps in the budgie app menu, and add to favorites. I suppose then you'd need a dialogue that asks you to choose the target panel (similar to XFCE).
Other suggestions?