HI
Whilst your Apple ID (presumably the @mac.com) may have been the original and been linked to @me.com at the MobileMe period and then to iCloud (@icloud.com) you need to keep to the same Apple ID through out (the iMessages server seems to treat them as different IDs to some extent).
In the Finder use the Go Menu > Go to Folder and enter ~/Library/Preferences
Find and Drag to the Trash com.apple.ids.service.com.apple.madrid.plist
On the iPhone remove those emails that are not the Apple ID in use.
On Restarting the Mac version you will have to re-enter the Apple ID.
If you then restart again you should get the pop ups to say what the iPhone is using (linking the iPhone number to the Apple ID)
Once you enable Text Forwarding on the iPhone then the Mac Version should generate and show you the Code to then enter in the iPhone's dialogue box to pair the devices.
If each Contact is turning red as you try to Send and reporting that the Contact is "Not Registered with iMessages" then you have a different issue.
This is caused by a partial login to the iMessages server and it seems it is one of those that only contacting Apple Support and saying you have an Account issue with the iMessages server from your Mac can it get sorted. (make sure you say it is an Account issue)
Of course it is the iPhone that is actually sending the SMS messages so it does need to have Carrier service at this point.

8:56 pm Monday; October 27, 2014
iMac 2.5Ghz i5 2011 (Mavericks 10.9)
G4/1GhzDual MDD (Leopard 10.5.8)
MacBookPro 2Gb (Snow Leopard 10.6.8)
Mac OS X (10.6.8),
Couple of iPhones and an iPad