Gambit asks you to gamble on what’s on top of the encounter deck, as he can range from embarrassingly bad to extremely powerful. A 2/2 is where you want him to be satisfied with the value. If there are 10 cards with 2 boost icons in a 30 card encounter deck, you’re about 70% to hit one of them. Not perfect, but consider that if you miss and only get 1 boost icon, you still got some value from seeing the top of the encounter deck, and you know exactly what the next boost and/or encounter card will be to plan accordingly. In particular, that boost card will only have 0 or 1 icons, enabling a safe flip to Alter-Ego or taking an attack without wasting a block. Then there’s the upside of sometimes hitting a 3-icon card! Not the most consistent ally, but a fun one for sure who should at least pull his weight in most cases, especially when the X-Men trait is relevant.

This has a nice synergy with Global Logistics, which lets you check the encounter deck before bringing Gambit into play.

Effectiveness aside, it's just good fun when you get to steal Universal Weapon :)