I still think they ought to scrap the whole 'tree' idea and just have the player pick from a diverse yet roughly equal set of possible skill choices.  The tree idea is outdated and bland and unnecessarily restricts replayability.  The entire game is assymetrical, so who cares if the choices aren't exactly even or progressive?  This isn't WoW, for criminy's sake.

I did like the 'trading card' like system in FE. Every level gives a random set of possible abilities, and choosing some lower-level abilities allows the next highest to become a possible choice for the subsequent level-up. "Uncommon" and "Rare" abilities sometimes could appear as choices.

Leveling up was sort of like opening a booster pack of Magic cards.

I think SK is suited for a more random approach than LH was.  Maybe part random and part fixed skill tree?

Can the same sov get different champions in different games?

That part I like and want to see kept. 

My issue is that the way it's implemented now seems less "fun" than LH for some reason.  I suspect it's a combo of a lack of epic loot and not enough passives that help to buff a character up.

I also think if you do an LH sequel, that having champions/sovereigns have their own tree there will be necessary as well.

What about a non-static hero tree? In other words from game to game a particular hero's tree isn't exactly the same.