I also think it’s just a matter of polishing, the mode column it’s a great introduction in my opinion. I really hope that in the future cameras will be re-introduced, setting the active one from the outliner it’s really handy.
Properties sync:
-As I already wrote, I think that for truly benefit the syncing with material properties, the material icon should be exposed at the right of the object’s name and not only in the hierarchy: even if material properties is not the main space for editing materials, it’s used many times also for changing settings like displacement, screen space refraction and blending modes, therefore it should be easier to access.
-I think that @radi0n’s proposal of syncing the object properties with the object’s text field and/or orange icon could be really nice and worth trying.
-I know it’s probably out of scope, but maybe also Force fields should have object data and physics icons, along with empties they are the only objects in the outliner that have no icons on the right. In this case, technically also other objects with physics properties should have the icon in the outliner (maybe for objects other than force fields, it should be only inside the hierarchy).
-BUG: Syncing with light properties happens only after we select another object data’s icon, otherwise it doesn’t activate. If instead, we click on other icons like modifiers, and then we click again on the light’s object data icon, it brings you to other properties editors.
And besides this, congrats Nate for all the work done so far! Properties syncing it’s a dream come true, and with all the other new features to come, Blender’s outliner is becoming a true badass 
!