You see, phantom definitely isn’t unplayable underpowered, more so outclassed. Similar to the smg-9 , they can both get the job done when it calls for it, but other classes such as fragger, nader, stoker can do his job much more easily without nearly as much risk. Now, phantom COULD be buffed in terms of just tweaking the number we currently have, and I have no doubt that would make him considerably stronger. In actuality, phantom would need something else in order to outclass these characters at their job in some regard, and if a separation of the emp from the cloak is off the table, then this will be extremely difficult.
I have been toying with the idea that deployables effected by the emp effect have a damage multiplier on them, effectively making them 1 hp, thus making it easier for phantom to take out camps, and easier to kill an aura and her station one after another. This coupled with a nerf to aura that restricts her cooldown as long as the health station is up could work very nicely for our katana-wielding weaboo master.