I know the 3D engine addition is a long way off and tactical combat even further but I figured I'd make the suggestion.

Basically an option to save tactical battles so that you can rewatch them or show them to friends. Say you had a cool fight against a dragon and you want to show it to a friend that also has the game. Since the battle would just be info like units stats, orders issued, and random seeds generated for outcome the files shouldn't be to large making them perfect for sharing.

Also it's unknown how tactical combat will be handled if the player chooses not to fight. Personally I hate how most games use a completely different set of rules for when the player fights vs auto calculation. Because it makes curtain units more powerful given which menthod you choose. I hope that elemental doesn't use this "cheat" method and actually really runs the battle behind the scences for a player who chooses auto. If it does and there is a battle recorder the player if interested can then check on why they lost a battle.

This could also be handy in multiplayer as sometimes players don't like sitting around while the other players have their battles. The players who don't have any battles that turn are often left out waiting thus most MP games insist on auto-calc to keep things moving along. Well with a battle recorder if the player has extra time on their turn they can spend it watching a battle that happened that turn or the previous turn to see why things played out the way they did.