I'd like to remove my phone number from my iMessage account, but still have my phone enabled to receive messages sent to my email address (also used on iPad, Mac). Is there a way of doing this?
You can remove your phone number from Messages on your Mac and iPad. On your Mac, go to Messages > Settings > Accounts. Select your account. Uncheck the box corresponding to your phone number. On your iPad, go to Settings > Messages > Send & Receive. Uncheck your phone number.
You cannot remove your phone number from receiving messages on your iPhone, because this is also where your text messages come in. However, you can set your email address as the default. This will guarantee that all new messages sent from you will show your email, and all responses will come back that way. Go to Settings > Messages. Select to "Start new conversations from" your email. I hope this helps.
If you want to remove your phone number from your iMessage account, go to http://appleid.apple.com and press the button for "Manage your Apple ID".