a healer. EVERYONE should have been a healer. stuck with malavai, mako, blah blah blah blah you get the point. i just wanna be a sith with my apprentise... or a jedi with her padawan... this is all i ask. and don't give me no hero story of "i never need heals derpherpderp" please. that's fine for you, but that's not the experience i'm getting T_T believe me, i wish it was.
Problem is, unless you want to burn through med packs like crazy, or play a healer class yourself, certain companions just do not work with say a tank or DPS. You end up for game purposes being stuck with one companion.
On the other hand I do like what you are saying. Would be nice say as a sith lord, to have an apprentice of your own, or as a Jedi knight or master to have your own padawan to train. Granted as a JK you get Kira and she is handed over to "train" nominally, though IMO should of just made her a knight in her own right and just let you two be partners.
But again, would of been nice as a JK or JC to have a youngling to train as you go along.