Yeah, oversaturation really hit the Batman and Spiderman lines hard. I'm like you; I have a bunch of kids and a limited budget so I can't afford to get EVERY variation of Batman with some funky swimming suit on or Iron Man with every color of the rainbow. Here's what I think the MU line can do to keep its longevity...

1. Keep the package art edgy and sleak
2. Keep making strides in accessories and articulation
3. keep diving into the MU universe while keeping individual variations to a minimum
4. Avoid cross-pollination with more mainstream lines (Thor, Cap, Iron Man).

I think a baf option, more accessories, better sculpts, especially females, include more larger figures to balance scale, offer great mail out and sdcc/nycc figures. And limit the # of variants to a minimum and try to get every figure from ML made into a MU figure at some point.

Hasbro has the license until 2017, so I'd be willing to say that the line will last until then. Look at what Hasbro does with Star Wars. They continue to put out fan requested characters, new sculpts, and repackaged versions of older sculpts, too. If they follow that formula with MU, they should be able to keep a pretty consistent customer base until their time is up.
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