Hank Pym compares favorably to most 2-cost allies, and he's about equal to most "just stats" 3-cost allies. He also has the flexibility to have cost 1 ("world's cheapest block!", and great for early turns in your Band Together deck) or cost 4 if you have spare resources to burn. He's even technically got a 0-cost option (thanks, Team Training).
A great ally who can find a home in any Leadership deck. Just don't try to reduce his cost ("a card cannot have 'negative'...cost", in the rules under Modifiers) or put him into play without paying his cost.