[Raine24]

The Versus packs would totally fit the theme, but after a while you're going to run out of characters that can carry their counterpart, imo

What about stage dioramas? Getting every figure in a wave would let you build a subway platform or forced-perspective fighter jet tarmac! It wouldn't add as much to the retail as an entire second figure would, and characters you don't like would feel like they're adding onto something bigger and more grand, as opposed to an anchor around the neck of the character you really wanted

Or you could have a hefty amount of effects pieces spread throughout a wave. Flaming fists and electrical arcs and wooden boxes in the process of breaking apart, so someone who wouldn't even consider a figure of Hugo is suddenly eyeing those hadouken effects and considering picking him up