Disable "Set Angle" for some bullets

Is there an action where I can disable the "set angle" property on some bullets, but not others?

Also, is there an option where we can disable a bullet behavior in the property bar? Like how the "Sine" behavior has an "Active on start" property.

If the bullet behavior doesn't do what you need, it's straightforward to reinvent it in events using the 'move forward' action and some instance variables to represent speed, angle and so on. That's the best thing to do if you need customisation beyond what the behavior provides.