What does Skype use all those permissions for?
Your accounts - Skype acts as an account authenticator the way Google does; most likely used to easily store your Skype username and password
Your location - probably for statistics and some location-based features
Your personal information - allows you to directly call a contact's phone number, as well as their Skype account, from the contacts application
Phone calls - almost every application needs access to to this section in order to get the phone's unique ID. Skype also needs this to know if the phone is in a call.
Storage - probably to store cached data
System tools - all of these allow Skype to prevent the phone becoming idle during a call, as well as sync contacts


All other permissions should be obvious.