You can also not put in username and password for a Google account. Without authenticated account, Google Play Services won't work. What you can do, is to inst

You can also not put in username and password for a Google account. Without authenticated account, Google Play Services won't work. What you can do, is to install apps or plugins for CalDAV/CardDAV-like services. The account system works with any generic account, not just with Google accounts; you can implement any service you want talking with any protocol you want. You don't need Google Play Services source for that. Removing apks for android installation is cannon for sparrows. Remember, /system is not only for running the system, but also for factory reset/recovery too.