So how does that AVX Captain America hold up under pressure at 200, or even 100 points?
It's a gamble to field anybody at 100 points with only 5 clicks to back them up - considering the number of figures that can dish out 5+ in the under 100 point crowd, this is asking for a quick KO. That said, Cap has enough going on that not only can he be fielded at 100, it's almost always a better starting level over the 200 point line (with only 3 more clicks of life, and not much in the way of better stats).
What sets cap apart from others in his point level to clicks of life ratio range is his Super Soldier trait that lets him pick a defense power at the beginning of the turn. As he's a ranged attacker, he can keep back to the edge of the fight and make use of his repositioning Leadership sp and Empower while giving him an optimized defense. Improved movement to reposition and shoot will make pinning him down difficult, and Willpower on his full dial stretches out those 5 clicks.
At 200 he's noticeably better with more damage reduction and slightly better combat values and he has more options with Leadership, but consider that special attack Incapacitate: I'm less likely to use it at 200 points when I've got a natural 4 damage up top.
With all the Precision Strike and Penetrating Damage available, Impervious and 3 extra clicks just doesn't feel like a worthy investment (consider that 5 out of 6 of the AVX X-Men starter figs have access to damage penetrating powers). When you're fielding those 700+ point Avengers teams, then maybe it makes sense to pull out the stops and drop the double-C-note Steve on the field, but anything lower is just asking for trouble.
The X-Men don't have a Super Soldier equivalent (Wolverine is playing on the Avengers side) - at best they have Scott Summers who has some similar Leadership abilities between his WatX uncommon which negates TAs, and his starter kit version which can pull tokens off the ~300 point Phoenix figures.
As far as team leaders go, Cap has the edge over Cyclops - between support powers like Perplex and Empower, and sheer durability, as well as options between defense types (ES/D or CR) it's hard to argue against 80+ years of military experience.