I'm hoping they do a 2-pack per film. The Wolverine & Mystique one looks like it's for X-men (thank goddess it's Rebecca Mystique, not JLaw), and the Professor X & Magneto is obviously for DOFP.
They need to do a 2-pack for X2, with Nightcrawler. And I'd personally pair him with Storm as their storylines went along nicely. X2 also happened to be Storm's best look.
I'd buy a 3-pack with Famke's Jean, James' Cyclops and Halle's Storm from either X-men or X2.
I don't know who I'd do for TLS. They can do Psylocke & Archangel for Apocalypse.