Yeah man, I'm having the same problem. I want the leader to be my 'daughter' who is an adventurer and organized so that the entire stack uses her movement points, and she's also the one with the teleport spell. Instead, the leader is my warrior champion.

We seriously need to be able to target dudes within a stack.

And iss changing the leader of the stack even possible?

That's because noone leads a stack in a city. Inside a city, the bunch of units are not considered an army, just a bunch of units. Whoever enters the city last will be added to the end of the list. Outside, units given the same destination square will merge into an army and one will become a leader(i believe it is the sovereign, then the highest level hero, then the unit with highest combat rating, whatever applies first).

You can still have a leaderless stack outside city tho - generally when two units travelling to two different destinations just end up on the same square when they run out of movement points (or when the army already reached maximum members(12))

I think a really easy way to implement re-organising a stack on the map is to be able to drag a circular portrait of the unit on top of another unit (or after the last unit for the unit you want to be last), and it will be moved the space before the one you dragged it onto.  A bit like how you drag an item from the inventory of one hero to the circular portrait of another hero to transfer it to that other unit.  I think this would be a really simple and effective way of ordering units in the way you, the player, wants.   What do others think?

Also, is there any way of transferring equipment one unit has picked up with one (hero) unit or bought in a shop, to another unit?  I haven't found any way yet.  If there isn't any way currently, I think there needs to be.  What do others think?

Best regards,
Steven. 

I find it much more annoying when the ordinary units become leaders. I had one army I couldn't teleport because it was level 5 and ended up leading even when combined with champions. It is really humilating to have my champion be part of the Peasants's army.

would be very nice, but it is not on my wishlist for the next update.  there are simply too many game crushing things that need fixed first. 

having the ability to select who leads a party would be nice. but you can resolve some of these issues by simply having your casters/children fight enemies solo (or as a group of casters) so that they are 1 level higher than the rest of your troops (it really doesnt take much time to do this as long as you are not too far into the game). 

a formation option would fix the tactical battle problem, but again this is an annoyance more than anything else.  the slow pace of tactical combat is far more important in terms of making this game playable.  if combat speed were faster, moving your melee to the front lines would not be so annoying.