Launcher without home screen? Is there a launcher software for my Android device (in this case Galaxy S2) that doesn't have a home screen, but only the App drawer? 

If I can give example it would be an iOS; you unlock and you are instantly on applications. The reason for this is I don't really use widgets at all, and I don't see the point in having a home screen only for apps shortcuts if I would have only menu (app draw).
Espier Launcher might be the closest thing you can get to an "iOS experience".

I gave it a test run, it does not have an app drawer...  It's pretty much exactly like iOS.

Note: Espier Launcher is no longer available in Play Store since 2013.