I feel that a scarcity of resources, such as with Source Points, would certainly help to alleviate this issue quite a bit, if not completely. What say you to this: by the end of Act I, you find one Bottled Inferno lying next to the Houndmaster's Crossbow, and one frost grenade on Magister Captain Trippel. Both guaranteed drops, no chance that you'll end up with tons of CC by happenstance, and you're never missing out on the opportunity to get these items because they are placed loot. Would you feel that they are balanced then?
Also... I personally think that Charm grenades and arrows cross the line. They are way too powerful, period. Even if they only affected half the targets they hit. Even if they only had a 50% success rate. Still too strong. No thank you.