Bug/Fighting has some interesting resistances so I'm happy that Heracross gained a lot of bulk.
Keep in mind that while the mega form doesn't get a Guts or Moxie boost, there are attacks it can only use with Skill Link that have significantly greater base power and accuracy. That, alongside its massive defense buff, makes it the far more reliable Pokemon and I would use it over vanilla Heracross any day of the week.
I would probably run a no nonsense set consisting of Pin Missile / Close Combat / Rock Blast and either Bullet Seed (to beat Jellicent and Azumarill) or Earthquake (Aegislash). I don't think it's going to require a Swords Dance boost with that absurd attack and coverage.
It needs help mitigating its low Speed, though. I'd be surprised if anyone could work Mega Heracross and Sticky Web support into the same team due to the type conflicts running two Bug Pokemon would bring, but paralysis support is always welcome. I can see some decent type synergy with Barbaracle who also acts as a nice offensive check to Talonflame and lures in Grass types which Heracross gobbles up.