Think this rune in it's current iteration has little to no value and there is no situation where this rune would/should take the slot of any other available rune in any situation IMO.
Some possible changes that could be considered below:
Only require the owner to have it in their inventory, not equipped for it's effect(s) to work (this should apply to some other runes TBH, not just this one).
Consider making it so all mobs can't see you while invisible (bosses and champions should still be able to see you).
Make it so only counter detect, not regular detect breaks the user out.
Remove the 10-second cd that prevents spell casting after use.
Obviously not asking for all 3 to be implemented but just some ideas. Change 2 and 3 especially would allow the class to lean heavily into a true "assassin-style" game play while also allowing the user to get resets/exits in combat more effectively and would IMO make it worthy of a rune slot in PvP situations.
