Speaking for graphic designers who use Create:
Cartesian plane lines showing the center point of the slide (in Grid)
Grid currently "snaps to" the top left corner; doesn't help if you need to "ground" the object
Guidelines that appear when you click and drag an object, to align many independent objects together
Would love to see adjustable grid opacity.
Agree with this! I've been drawing lines manually and then deleting them. Very redimentary.
Ability to lock media objects in place on the slide.
These are enhancements that designers have communicated are absolutely necessary to do their jobs well; minimum expectations to be competitive with other authoring tools.