I would like there to be 9 factions in Heroes 6: all the factions from Heroes 5 with minimal changes, plus a Swamp faction.
And more neutral creatures!
And in general, if a miracle happens and they change their minds and release the last expansion with a Swamp faction and neutral creatures, I won't even need Heroes 6!
It's just a pity: since they added the 8th faction with the Barbarians, they could have added the 9th, or at least neutral creatures like Gorgons...8(
I don't understand why you need so many neutral creatures; I think it's better to have more castles and factions, and a large number of creatures with 10 or 5 levels, 2 for each!