Well that depends on the point of view, if you're okay with Cocoapods being designed to modify your Xcode project, etc etc. That should be fine. Again, all of this is a pretty big overhead to just 'script out' something.
The Xcode project integration is optional and can be disabled by passing --no-integrate to the install. Like so
pod install --no-integrate
Nothing. Neither with Carthage. The problem is that they rely on the project configuration (Cocoapods requires also an xcode workspace on top of that). It's a bit overkill for just a script.
Oh, I just reached the point where Ayaka talks about Carthage. That's a pretty straightforward solution, nice.