I completely agree on the pre-Socratic point. Where's my man Parmenides? But in fairness, many pre-Socratic works are so fragmentary that it's difficult to even consider them works, nevermind philosophical works. Thus they typically fall under the purview of Classics departments. It's unfortunate that they're not taught more broadly and in a context that's more appropriate to their subject, but Classicists are probably the best equipped to handle these authors, given how time has present them to us.