Ideally you'd want to trace the application misbehavior to a root cause in the application itself, but I think we've all been in the situation where "turn it off and on again" is an easier solution. :)
I wonder if this could be a feature request for App-AutoScaler? It already has access to the metric types required for the operation, but it would need to be able to take a policy action based on those metrics other than scaling up or down (e.g. "adjustment" : "restart" ).