CoA is far better at keeping Molten Core up than Corruption. (ticks every second instead of every 3 and uses less GCDs).

Unless you have 2p T7, don't bother with Corruption, it doesn't add that much dps.

Other than that your rotation looks fine, I'm assuming you're using Glyphs of Conflagrate, Imp and Immolate, which would be the right glyphs, though you might use Glyph of CoA instead of Imp, they're pretty even.

While I'm still sure Destruction should scale better than Affliction, I found the dps especially on bosses so dissapointing I'm back to affliction, it would just be nice to get Dual Spec, Felguard/Emberstorm for heroics would be nice.