TPF Alexis said:
Once you get that fifth yellow for Kitty, that combined with leveling her up to something like 330 or so should roughly double how much she's boosting the Strikes, but not mess with your MMR. Also, a Support that Fortifies friendly Specials can really help. Element Guns, Chimichanga, Lockheed, not sure what ranks they need to be, but I know they can all do the job. The Milano on Grocket is also a significant help. Doesn't need to be leveled, 1* is fine. All you need from it is the Synergy Perk Countdown giving you an extra hit with all those Strikes.