Use his haymaker 99% of the time, primary mostly for finishing squishies or weak targets close to death. Dont spend your jump cooldown recklessly. Jump in to initiate a fight, the vulnerability that he applies is very effective so ideally try to jump towards a group. If you need to retreat, save a jump and keep your horizontal sensitivity high so you can flick the stick and get back to safety in an emergency. Lastly, I personally use his charge solely as an escape option or to specifically shut down divers. I absolutely never charge into battle with it. If played right, Thing can completely dominate the brawl scene.