Lets see... we banned Gallade in UU due to his offensive prowess. Heracross is even more powerful than Gallade, due to the 5 extra speed and STAB Megahorn. And unlike Gallade, he loves to be burnt. He also has excellent coverage. AND Swords Dance - the thing that really got Gallade banned. So if we banned Gallade, I really don't see Heracross staying in UU for long, if it even gets there.
Cresselia would be GOD in UU. No Tyranitar/Scizor to ruin its walling(although Scyther might plough through it). I only really see Mismagius setting up on it.