I might not have done a great job of explaining what I'm going to offer up on the store, so I'm going to outline it a little more specifically here. Please let me know if there are any flaws in my logic. I appreciate all of the responses I've gotten so far.
I am creating a zombie pack that will include somewhere between 12 and 20 different zombies with animations in it (final number undecided). All zombies will have the same animations (12 total plus a frame fore laying dead).
Because I don't know what sizes people need for their project, I am including the different "sets" shown above. The original resolution I work in is 600 x 600. I realize that is way too big and never intended for the developer to use that big an asset. I'm including it only because, if they can't use the 3 other provided sizes, they might want to shrink the art on their own before importing into Construct 2.
I have 2 versions of the full resolution art: 1 with Lines and 1 without. I've included both because omitting the lines helps once you hit a certain point in shrinking.
I am also providing all of the art in 2 different color schemes. The top one is a color scheme that all of the zombies will have a set in. This way, you can randomize pallets and have it set across all zombies when they spawn. The second set is just a color scheme that I came up with if you just want to import the art and not have finer control over the colors.
All of the art has a lot of transparency around it. I wasn't too worried about it because I figured people would just auto crop it out in Construct 2 after their origin points were set. If this is wrong and I should still be worried about power of 2 assets, please let me know.
And if you want a preview of the animations that will be in the pack, I have some previews up on my instagram: http://www.instragram.com/needyourdisease
Thanks again for your help.