This is more contemporary but shows the two rails with stand off idea.
Q
Even though this shows the spindles continuing behind the lower handrail it gives you the idea of two stacked.
You could replace the handrail with a wider one like this. You could paint the spindles a dark grey.
If we added a new handrail raised off the current one by supports it could look a little like this one were the metal support is every few feet.
'This shows the lower level idea as it es to the ceiling. This is the latest cool stair rail look.
Lower level steps.
This is more contemporary but shows the two rails with stand off idea.
Q