^^Me too, if I'm not playing a mage myself...I have made Morrigan a healer^^
To me, shape-shifter is just.. ho-hum.....
Manual of focus mod
It is a matter of personal taste, and built right, shapeshifters can be one of the most effective specializations and add a lot to a mage build. Not to mention it's a lot of fun seeing a Swarm mage take down Cauthrien.
Morrigan can be a decent healer, but she's significantly behind on spellpower/mana/creation spells and needs to do a lot to catch up to Wynne. There are always spirit healers around, so it's not something I think much as far as building her toward that role.
You can use healing potions to do that sort of healing instead of use a support mage, but there are a lot of Creation spells that can be useful to a party. I think Shale adds a lot to a party, but it's a tough call on having a support healer or Shale as the fourth member of the party.