This is what I am thinking of. Replace the current system with something like this (but right side up so you can see all points) but with transparent blue or red glowing lines that shows up behind the enemy.
A point on the pentagram will glow as you gain each signet going clockwise. Once you have all 5 signets the pentagram will catch fire and blow up once the mark is erased. The pentagram will always be seen behind the enemy facing you and only seen by you (so as not to confuse other Assassins on the target).
The current system... well it's just bad. With the graphics listed
here, I don't know how anyone can tell, especially me since I'm colour blind.
Being colour blind I don't always catch the same things other people can see. Too many things apparently just blend together for me to separate visually.