Aussie actor Jai Courtney (Spartacus) is an action star in the making. He's taken on big Hollywood roles in Jack Reacher and is co-starring in A Good Day To Die Hard with Bruce Willis. There is talk that Jai would be continuing the Die Hard franchise when Willis exits. I think he's the type of actor Edgar Wright would be considering for Pym or Lang. It's been mentioned Ant-Man would be a high-tech spy film so Jai could be in the right age-range for something like this. He's also new enough that he doesn't have that many commitments to other projects so Marvel could wrap him up in one of their lengthly contracts.
Pair Jai up with the uber bubbly Alison Brie as Janet van Dyne and it's a perfect combo for an Edgar Wright film..
final trailer for Die Hard 5