Ground connection between local and global GND in oscillator layout
The way I have had the best success with is to essentially Island the oscillator and make its only ground connection at the ground pin closest to the oscillator, having the via that connects it to the main ground plane be on the opposite side of this ground pin, I would aslo reduce the size of this island to only directly about the oscillator, 

In this case I would also look into islanding the second layer plane directly beneat the capacitors and crystal and dropping a via ring around it to essentially cage it in on all sides to that one pin, 

This makes a sheild for the crystal on all sides, so any fast current spikes cannot easily couple in,