Q: Best way to set up multiple iPhones within family?

We have 3 iPhones in our family, and we've always just used the same Apple ID  for all three devices.  I understand there have been some changes to ios recently, and this strategy may not be the best way to have things set up now.  I have started seeing some strange behavior between the phones, with calls/texts showing up on other people's phones.  Doing some research, it seems as though maybe we should all have separate Apple IDs and then go the family sharing route, so I was hoping someone could clearly explain how I should go about setting this up.

Right now I have my Apple ID that we all use for purchases, and it looks like we are using an old @me.com account for our iCloud account...which i am guessing is what has enabled us to share calendars, see all of our devices in Find My iPhone, etc.  My Apple ID is not the same as the iCloud account address.

I work in IT, and generally consider myself a pretty sharp guy...but I will admit that all of these Apple and iCloud IDs confuse me...so any help is appreciated.  My main goals here are:

• Be able to see the locations of all the people in my family
• Not have calls/texts/etc from one phone showing up on others
• Be able to share and be aware of iTunes purchases across all devices
• I have Music Match set up, on my Apple ID (I think...), so I don't want to lose that functionality across all devices
• Share a family calendar as we do today (and hopefully not lose what is currently set up)

Thanks in advance!