I don't get Phalar Aluve

I see everyone is always going on about how good it is but I always find myself dumping it quite early. Yeah the song/shriek feature is great and having a finnesse longsword makes it probably the best weapon for dex based melee characters who are not dual welding (or have the feat) but it costs an action. Like a whole ass action. I never had a character who had nothing better to do in the first round of combat. Like if it's on a damage dealer, I'm skipping my opportunity to deal damage. If it's on a support character, it contends very heavily with staffs and blood of lithander (esp. In act 2).I just don't see the use case for it. You could start it before combat, sure, but then you can't stealth into combat so you miss a surprise round, so it ends up costing you the a whole round rather than just an action. I had one character that was specced into 2 weapon fighting with the feat and a couple of fighter levels so I could use it with action surge, so I could use it up to very late in the game, but that's it. I had to have a very specific build to make it even remotely feasible to use. How do other people use it? How do you mitigate this?