Apologies if anyone else has mentioned this but the ability of archers and wizards to use heavy armour types has me a bit perplexed.
Traditionally archers didn't use much in the way of armour due to the lack of flexibility this would cause. Trying to draw back a bowstring and aim using full plate, when thinking about it, does seem somewhat impossible. For much the same reason, traditional fantasy restricts armour use for wizards, i.e. the restriction in movement for spell casting. However there are no restrictions on what type of armour archers can wear in this game, nor for spell users. It somewhat struck me that my spell casting, arrow shooting sovereign clad in uber heavy plate was slightly absurd as were his hip shooting, plate clad groupies.
Some suggestions if I may.
1 - Bow carrying troops should be restricted to leather amour at best (the mechanism for shields and 2h weapons comes to mind here).
2 - The mana use box greyed out if armour is worn at all by heroes (they do have spells after all).
I would also go a bit further and restrict the type of weapons that spell casters can use to simple ones such as staves and daggers but I'm a bit of a purest when it comes to fantasy.