- targeting enemy = single target damage
- targeting ground = AoE
I would rather simply add Another spell ... Chromatic Orb with AoE, and Chromatic Orb without AoE ...
Or even easier, implement Homebrew Metamatic that will reduce damage by dice (useable only for spells that have at least 2dX, logicaly) to AoE effect. :P
Make it cost nothing ... and make it useable with any other metamagic.
Voila!

Everyone happy.
- Abilities that target one or several individual targets should do nothing if they miss. (e.g. fire arrows)
- All abilities with AoE effects should show the size of the AoE effect. Of course the effect can get bigger, like when you use fireball on an oil lake, but at least you should see the area that gets definitely affected.
- There must be ways to cause elemental damage to enemies without damaging nearby allies. Normally a fire arrow or a chromatic orb should only damage the target if it hits, nothing else.
+1000
I would just like to add that tooltip should also state that there is AoE effect, and how much damage that effect will do.