Include Select Similar Objects button and dropdown in the Properties panel
Please add Select Similar (same, colour, stroke, etc...) button, to new Properties panel(2018). And option for aligning one single object to artboard in Properties panel, would by fine too(without entering Align panel).
This button is much more convenient than navigating Illustrator’s dropdown menus, but I don’t want to keep the Control bar open only for it.
A button directly below Start Global Edit in the quick actions section of the Properties panel would be a very natural place to put it, since those two buttons sit right next to eachother on the Control bar.