Oops... Just noticed icon size in the most obvious place, on the Geometry tab of Panel Settings. Sorry!
It would be cool if icon size could change automatically with panel height - it would be easier for non-geeks to tweak. But it's fine for me.
tint2 still wins on these points:
- I can change icon size in tint2. (In LXPanel, I shrink the panel height, but the icons get cut off at the knees.)