I would like to be able to transfer items between champion stacks without having to move the stacks manually -- similarly to Master of Magic. This could come with a cost of mana, or gold and perhaps a delay, or a chance of the item being lost.
On a related note, it would be pretty cool to be able to trade items as part of a diplomacy offering. I figure that the base value of an item could be similar to its sale value, but there could be a significant bonus if the AI player was "interested" in the artifact. (He could use it and it was better than his current equipment.)
The option to show yields on tiles should be the default.
Diplomacy in general feels a little weak. I never feel like I am getting anywhere with neighboring empires... I am just marking time and trying to get what I can before going to war. It would be nice to have more diplomatic options. For instance, giving gifts for small relationship boosts, entering into defense pacts, and even trading ownership of nodes (my fire for your death, for instance).
Even large maps feel very small in that you quickly run into other kingdoms. I read somewhere that there were memory issues with larger maps, but if these issues could be solved, larger maps would certainly enhance the game experience.
Turtling seems to be a poor strategy in general. The AI is pretty aggresive with sending pioneers into your territory and declaring war. Though I don't think this is a bad thing, it does make the victory conditions other than "kill everyone" sort of pointless. Perhaps a few more techs and buildings can be devoted to city defense and securing your territory. I could see a tech that allowed you to build an outpost that actively stopped your opponents from walking through without you having to scold them. Or perhaps a tech that greatly reduced the wage of garrisoned troops.
Anyway, FE is turning into a great game. I am very excited for the next beta and the eventual release.