only thing I would change is drop the top by about a quarter of an inch so we can read the label of the paint.
What about just attaching the top plate to the bottom? The drilled out areas of the top plate look deep enough to keep the bottles from toppling.
I would really like to see stacking and wall mounting capabilities on these paint holders. The ability to buy a set or two for Vallejo (and other dropper types), another to stack on top for Tamiya, another for Lifecolor, another for my Humbrol/White Ensign tins, another for my AK bottles, another for my Mig Productions bottles, an extra tall one for my glues/decal solvents/etc... you get the picture. Mounted on the wall and out of the way. I can then glue on some magnetic strips on the front of the lowest one to mount my tweezers.
Yes, dreaming out loud.
Regards,