Works well with any cut glass too.
Do first check the tubes you want are available in 6'. In practice, there's a wider selection available as 5' tubes unless you're buying in multiple palette quantities.
When I looked at the picture, I thought of replacing the halogen bars with surface-mount perimeter wall washers, probably need to be positioned a bit nearer the walls.
If you go into a retail store with wall display units, you will often see they are lit with recessed perimeter wall washers, which are so glare-free you might not even realise they are lights or switched on at all, but you will notice the high illumination of the displayed goods.
There are other types of surface mount wall washers, but you will start to pay heavily for style. LEDs in fluorescent tube form factor which are directional are starting to become popular, but it's probably too soon for you on the ground of pricing and colour quality yet, although I'm sure this will come eventually.