You can use separate AppleIDs for iCloud, iMessage and iTunes - you just need to create unique AppleIDs for the iCloud accounts if syncing contacts that way (you will need an email address that is not already registered as an AppleID though to get another AppleID).
Apps are different: purchases are tied to the AppleID used to log in to the store to make the purchase. So you can create another AppleID for iTunes as well and use different ones on the different phones, but any apps you have already purchased with your existing AppleID are permanently tied to that AppleID.
So, unless you are sharing apps, content and such, there is no reason to use the same AppleID on each So the simplest solution is to create new AppleID(s) for other devices. If you need an email address to do that, just get a gmail account (or any other free email account).