I do like myself a good artillery barrage but not feeling it with UG. I've yet to fully look into the details but :
1) I feel round shot is useless, it should really hammer morale when hitting from a long distance as huge balls of red hot iron plough through ranks kicking up dirt and stone as fragmentation. In my experience I don't really get a chance to engage in long shooting because of FOW is too low, plus it's too inaccurate and hardly causes casualties. I'm play testing as I write and a battery of 4 cannon hitting a mass of 2000 men made 2 casualties, if it makes 1 casualty, the round will by it's nature make many more as it punches through the ranks.
Flank shots with this ammo should be absolutely devastating.
2) Shell is my favourite and I always put my artillery on that setting, sometimes it only kills one or 2 men even though the whole battery hit.
3) Canister is nice but I find the enemy wildly outflank a battery - it seems to take them an age to actually touch the powder for some reason and they end up wheeling the cannons around in a circle, then routing. I find myself thinking "for god sake SHOOT !!!"
4) Cannon wheeling is really annoying, as mentioned above the canister shot. I know I can use the hold command (be nice if the GUI was say, red, when this is selected instead of a slightly lighter grey...) but this micro management of the artillery is frustrating. When they hit 100% reload they should be ready to fire, instead of a 5 second pause, then shuffle, pause, shuffle - rout. Keep up the good work, very promising game