[kostej]

It's quite a difficult question.

IMHO what did not work:
- while comic 2-packs looked like a great idea on paper, it did not work. Often the figures had nothing to do with attached comic, very often the story in comic was difficult to follow if people did not know what happened in earlier in the series etc. So drop the comicbook from the pack.
- incompetence in characters selection - not completing some of the most iconic teams is such a shame. The same goes for movie lines - I will never understand how it is possible that we did not get major movie villains like Malekith, Ronan, Kaecilius, Yellowjacket...? What was Hasbro thinking? How the kids should have played with their figures when they had noone to fight against?
- distribution - thousands words were already written about it. Use your e-shop fully. For the love of god please permit shipping to Europe. Learn from LEGO company.

IMHO what could work:
- 2-packs - they are smaller, 20USD price is fantastic - kids can play their stories just with one box purchased. 2-packs offer lots of possibilities - hero vs. villain themes (Thor/Loki), thematical packs (Iceman/Blizzard), different forms pack (Hulk/Banner, Emma Frost normal/diamond), generations pack (Captain Marvel/Kamala, Hawkeye/Hawkeye) etc...
- vehicles - motorcycles, Kang's chair, Deadpool's chimichanga van, Punisher's van, S.H.I.E.L.D. cars, Lola car, Fantasticar, Milano spaceship, Quinjet, X-Men Blackbird
- giant figures - usable both for ML and MU collectors - Kree sentry, Goliath, Giant Man, Titan, Stature, Devil Dinosaur, Venom T-rex...