The per mini price is really good actually. About $3/mini if you buy the core set at retail. The expansions are a bit less of a deal, being about $10/mini, at retail. Then the minor expansions basically only come with 1 mini (and MAYBE a piece of an armorkit, depending on the expansion) so those are about $30/mini.
HOWEVER you are also getting quite a bit of game content for each of those, what with the gear, events, innovations, challenge scenarios, campaigns, etc.
The best thing to compare it to, would actually be Super Dungeon Explore, or Dreadball, both of which are around $100. This is what Poots was planning to charge, but after he started adding content to the core game itself, with stretch goals, he had to choose to either raise the price, or cut out content for non-kickstarter customers. He choose the one that wouldn't require chunks of the game to be ripped out because people might not have had money by a certain date.
tl;dr, yeah the pricing is pretty reasonable, considering the kind of game it is.