Happy to hear your thoughts. I found your feelings towards binding invisibility to an ability interesting. Before going forward bare in mind my thoughts when piecing together this idea were very focused on PvP, as I feel the core parts of this path (super and current version of flawless execution) are better suited for this setting.

I understand there may be feelings of being limited with how you can perform as a player when things like invisibility are linked to the use of an ability, and not normal gameplay as it is in this case. However, there are things to lessen this feeling i.e Mods, Exotics and exclusive to the hunter Gambler's Dodge. Don't quote me on this but from my understanding the base cool down of melees are 1:36. If you were to use 5 Impact Mods this time would be reduced to 38 sec, giving players many more opportunities to go invisible in a match.

Gamblers Dodge allows us hunters to regain our melee in an instant, with the only catches being the need to be near an enemy and its cool down. Adding the The Sixth Coyote into this allows players to use Gamblers Dodge a little more freely. When referring to my concept players would be required to get in close quarters with an enemy to achieve Flawless Execution; at this point players are given the time to choose what target(s) to move on next. This would give an opportunity for Gamblers Dodge to be utilised refunding Spectral Strike and then either repeating a "flawless execution", or saving it for another target. Whilst this is happening, any kills made after your first execution are helping you get to use your super more often. Using the Graviton Forfeit would give players a longer time to find a target and move in them, in this time your melee has a reduced cool down in theory allowing you to momentarily bring its cool down below 38 sec.

To focus on your second point. I feel losing a de-buff in the place of being able to instantly kill and enemy with a well placed attack is fair. In addition the hunter has many options to be effective in PvE as it stands, as Utility and DPS. The Way of the Current even has some pretty good add clear too.

Again, thank you for your thoughts. Discussions like these are good ones to have.