I did the same thing you did, started out as SMN, and slowly transitioned to SCH later. SMN definitely needs the boost more than SCH does, so I'd say keep your points in INT.

Even without the extra 30 Mind, I've healed T5/Levi EX with no issues on my SCH at i91. The main thing to being a successful SCH is to have your fairy on Obey, and use her abilities as if they were your own.