Haven discussion.

I've tried it, but it's hard to play. For some reason, the Castle lags (it's the only one for me)
The Castle is weak because practically all heroes specialize in units.
They work great against creepers, but have nothing against an opponent other than griffins. Their only hope is Training, but there's nowhere to get money. Upgrading a peasant to an archer costs more than buying several archers.
Competitive only on wealthy maps; on others, they can be disregarded.
And consequently, they suffer from ATB. Since griffins don't always get the first turn (though they should always), losses are practically inevitable. Growth is small starting from Griffins. Priests are a completely pointless unit. They aren't inclined toward magic; they prefer defense. The hero is a terrible cheater with his Holy Charge.
But if Tyris, Orin, or Christian make it onto your list of favorite heroes, then that's your choice!
If you have any specific questions, ask and I'll answer.