See what y'all think...
I think the size contrast may be a bit more pronounced. However, making secondary buttons smaller is bad, they're hardly visible already. Especially the raise/lower buttons are hard to decipher, they're too complex and dark, perhaps someone will have to redraw them eventually. The main toolbar buttons may be made a bit larger, IMHO.
Also, can we rearrange the toolbars so that the corner is occupied by the secondary toolbar, not the primary? Rationale: secondary toolbar may ultimately need lots of space for all its controls, so every pixel counts. The primary, on the other hand, is unlikely to grow significantly.
And if you do that, can you provide a bit of separation between the toolbars by moving the primary one to the bottom a little? Ultimately I would like to see in that interval a "handle" that will let me drag the toolbar e.g. to the right edge or make it floatable, but until then, let it be just a few pixels of empty space.