It would be great if there was a minimap in the lower right or left corner of the screen. It should show friendly and enemy forces and demigods as well as give off signals when towers are being attacked and allow for allies to ping locations.
The most annoying thing right now is the camera view. I strongly prefer to be able to move the screen by nudging the mouse cursor to one side of the screen instead of using the arrow keys. That way my left hand can remain on the action keys [qwer] and my right hand can focus on targeting and camera views. Also, being able to rotate the map quickly is important. Several times I could not get a good view to target a unit or even see regulus hiding behind the rook. In Company of heroes holding down alt while moving the mouse changes camera angle quickly. Something similar would work well i think.
Unit selection is also a big problem. It is difficult to target specific units, particularly when they are in groups of other units. It needs to be easier to select an enemy demigod for spells like snipe, fireball, freeze etc. Unit movement seems to be slightly buggy too. Telling my demigod to attack another demigod out of range will usually have him run up and start attacking, but if the enemy demigod moves out of range, my unit will just sit there and not engage anything let alone chase the target unless told otherwise.
This brings me to my last point: there needs to be more specific commands such as move, attack move, hold position and the classic rts commands. These are the most notable improvement ideas I have at the time and I'm enjoying the game a lot so far. Looking forward to playing more and to getting multiplayer rolling.