TWIN JEWELS - Suggestion for a new kind of unique jewel

Simple as that:
- You can place a twin jewel in one jewel slot on your main path
- as soon as you did that, you can place another twin jewel in any other jewel slot on the passive tree which doesn't have to be connected to your main path
- After that, you can progress your passives from the position of your second twin jewel.
- There will be red, blue and green jewels
- Twin jewels only work with their own corresponding color
- The use of twin jewels on the passive tree is limited to 2 per color (meaning you can use up to 3 pairs, filling up 6 jewel slots)

This would allow even more unique builds and I think it would be fairly balanced, because it fills 2 whole jewel slots (and therefore requires 2 passive point) without providing any stats themselves.