Seems like version mentioned by Yoshi will be good/OK for:
Area damage -- either better than overpower or used when TP runs low.
Snap agro -- don't have to target or line up for a cone. Hopefully more agro than Flash. Or if you're out of mana.

Not every ability has to be the best ability ever. As long as it has some reasonable use sometime, that's all I would ask for.

As for giving up the damage reduction from Inner Beast, there may be times when you'd choose Inner Beast instead. There may also be times when you know your teammates are going hard on area damage and you can't afford to spend the time doing something that doesn't build area threat. In that sort of case you would have a 3rd option beyond just Overpower and Flash.