Now, a week after the V16 release, I have similar thoughts. LayOut was improved so that's really nice. In SketchUp I'm struggling to see improvements to me besides the added inference option.
... I'm actually considering using a LO16 & SU15 combo at the moment because of the new interface & a few bugs in them that break my workflow....
I would be very very surprised to see a UV map/unwrap tool, quads, nested layers panel etc etc coming from Trimble in a next V17 release. If you, as a user, really need those tools - get started learning Ruby yourself or pay somebody to make the tools for you. My guess is: they are targeting the average user who just needs an interface to a pro-package (Revit, Maya, 3dStudio, Rhino etc) if they need the pro-tools.
...I hope I will be just as happy with a future update for SketchUp as I'm with this Layout update.
In the mean time, many many thanks indeed to the plugin developers over here that have added so many invaluable tools that make SketchUp a joy to use!!!