Windows Phone is not a palm-sized incarnation of desktop Windows. It is not designed to be heavily customizable in the same sense that desktop Windows is open and customizable. I used to be more of the "customize everything" type but now that I am used to WP when I have to use Android I find exploring lots of menu nooks and crannies in order to tweak everything to be a tiresome PITA. This is of course entirely subjective and personal. That all applies to the built-in experiences; apps can do what they want just like on Android, and some offer more exhaustive configuration options than others.

Some of the apps you mention exist on Windows Phone: Skype, AA, maps (native maps are from Nokia but several excellent Google Maps clients exist), ... your bank may or may not have an app. There are media players and e-book readers but I am less familiar with specifics there. You can check on http://www.windowsphone.com/en-us/store/overview.