Could you clarify what you consider a "STP loop" to be? The reason I ask, the purpose of STP is to preclude L2 loops, so if you have a L2 loop, with a correctly configured STP running, something is "broken".
Regarding "broadcast storms", to identify such, you need to analyze the amount of broadcast traffic, then determine what you consider a "storm" level of broadcasts. You also may need to determine whether the broadcasts are legitimate or not. Once you have all that information, you can determine what your next course of action might and/or should be. (Understand, any level of broadcasts can be totally legitimate, and if so, but the load is too much for your L2 domain, you'll likely need to break L2 domain into smaller L2 domains. [BTW, this is often the reason why we don't have huge L2 domains, even with switches, as they begin to break down due to broadcast traffic. {Also BTW, this is a similar problem even with unicast on large shared media, e.g. hub, L2 domains.}])
