Ok the TaskbarLines option seems like an optimal solution, thanks tons.. Seems like something that should be included in the Taskbar3 documentation.. ;)

So I've tried implementing that with the following results:

with...
TaskbarMaxButtonCount 1
TaskbarLines 4
... the taskbar displays only 1 icon and 3 blank lines below it.

with...
TaskbarMaxButtonCount 4
TaskbarLines 4
... the taskbar displays 4 icons vertically, each of which is 4x4 pixels in size and barely visible.

with...
TaskbarMaxButtonCount 2
TaskbarLines 4
... the taskbar displays 2 icons vertically, each of which is 8x8 pixels in size, and 2 blank lines underneath.

Any clues as to how to have a taskbar that is 1x4 icons in size, and all the icons display at 16x16 pixels?