HP ice on Rotom is a good suggestion imo, but it's not really necessary as baloon Heatran already revenge kills most DD dragons. Trick helps him to deal with stall teams that seem quite problematic for this team.
I agree that crunch>bullet punch is a good change, it's better to cover Jellycent and Reuniclus, though he's forced out by Terrakion. Despite being very offensive this team seems pretty weak to stall.
I disagree with your suggestion on Heatran, balloon Heatran does set up SR quite easily and as stated before it's his best bet against dragons, should they set up a DD on Breloom. Also, just a nitpick: when you suggest a set try to not put too many optional moves. In your example, protect and roar can make a huge difference between making Heatran set up fodder for things like DD Haxorus and allowing him to phaze effectively.
Hope this helps.
<ginganinja> can I add Pocket
<ginganinja> to his own blacklist
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