Thought of that one, too, but I would give it Strong Jaw, because, snakes.
Mega Weavile would be cool, making it an even stronger glass cannon, and/or giving it refrigerate.That should give the opponent more chills that mega glalie...
In the same vein, we could have a mega crobat with mixed offensive stats...like giving it 50 extra in special and physical attack, so everyone can decide what they want. Maybe with gale wings (or poison touch), just for fun?
And while we're at it, why don't we have a Mega Arcanine yet? That could make for some really majestic design...
Also, personal preference, but maybe make tungstrike's face a little more threatening. It's based of a sabertooth, after all. Unless you want to make a sid-like pokemon, too. That would be grand and hilarious