I mentionned this in a previous post, but have now done some experiments.
It is difficult to level up heroes past level 12 for lack of XP. I started a new game and did an early fight against a bunch of skelettons.
- sovereign with militia, spearmen, sand golem: 12xp for sovereign, 5xp for trrops
- sovereign with militia and another hero: heroes 5xp, troops 2xp
- sovereign, hero, both troops and sans golem: as above
Since the sovereign has +10%xp, I guess the real figures are something like 11xp for the combat, divided by the number of heroes.
Now,, as I already mentionned, this explains why heroes cannot level up seriously to keep in line with the threat level. It is worth noting that the combat with both heroes and one troop is seriously more difficult than the combat with sovedreign and two troops. More generally, untill level 7 or 8, heroes are always hard pressed in combat. And that always remains true when you keep your troops up to date: current troops are always much more resilient than heroes.
I do not know why that XP sharing was set, but it's a bad thing. In particular, it makes having more than two-three heroes worthless, since additionnal heroes won't level up by sheer lack of XP, or they will drag down the XP gain for other heroes.
It also means that there shoud not be more than one hero in a given army : this limits the player's choices.
I remember that in MoM, it was possible to win by using a hero army, normal armies or a mix. It was usually more difficult to use a pure hero army (as opposed to accept losing replacable trained troops.) I belive that removing that choice is a bad thing, especially since, like on MoM, late game troops are not significantly weaker than level 20 heroes. Just different, with more raw power and less tactical choices.
Yves