Ok, let's get this straight.
Decent cleave- ok, for 2 targets, but if there are 3+, other classes are better, and even at 2, some are still very close.
Quickly taking out adds - unfortunately Chaos Bolt's damage is shifted into Immolate, and is nowhere near as powerful as it is now.
Aoe is decent too - uhm.. nope. Cataclysm is on a long cd, rain of fire is hard to use AND not effective.
Demo, super strong burst aoe - ok, if you have a few imps out, sure. But you lose a TON of single target damage that way, and if you keep HoG -> Implosioning, go see the results
it's not strong at all.
Affli good at council fights - this could be true, but there are only 2 dots to manage and they aren't doing that much damage. UA needs shards, and sometimes you don't get any and next time you are overflowing.
Good aoe? Soul flame is good on paper, but it only deals damage when something dies. And guess what, if adds are already dying it's just pure meter-whoring and overkill.
You are talking about Sow the Seeds + PS? Ok, you found something decent about warlocks, congrats!
Also, PS is on a long cooldown, and SoC has a long ass cast time, has a travel time, and a detonation "time", so you can't just spam it.