As for what I would like to see.......
25% or so of player characters/NPCs, at least one of each new race that has appeared since the last set. Minis with less visible weapons or such would be cooler as they could be an implement user, or warrior with weapons/implements not drawn.
20% or so of classic monsters like dragons, undead, orcs, goblins and such for those jsut getting into the collecting/mini hobby?
25% monsters of a variety of types similar to ones already released in older products, either slight molding changes or repaints. I have no problems with repaints. Maybe taking old rares and downgrading them to uncommons or such would work. Do make them different though, to keep the old ones rare.
20% monsters that have come out since the last expansion. With 1-2 sets of minis a year, this is a lot easier than it used to be. Draw from Revenge and MMIII
10% of oddball monsters, either named NPCS or just whatever odd things are running through the designer's minds. No official stats for such creatures need exist.
Yes, this is aimed at everyone, but mostly people who have not bought a lot of them before. Those with extensive collections are much harder to please. It is better to aim at those who are new or casual to minis.