I am going to geek out again but someone else out there said the same thing about video or RPG conventions (like D&D, WOW, Final Fantasy). So maybe someone else will get this reference but magic users are often classed as offensive magic users or healers, both who cannot do much physical damage or take much damage. Then you have hybrids like Emma who heal, fight and can take a licking and keep ticking. but not as much offensive magic. Hybrid classes are hard to balance right in a game so then you get someone overpowered who does it all and better–like Rumple. but sometimes it does not work quite as well in a group where you need to protect or heal others, because the skills apply mainly to yourself.
So I do not expect Regina to be very good at healing magic–it is not her “class” in a manner of video game speaking but as it is a show, they can give her abilities for it if they want. I think we did see her do some positive things with magic on occasion, or at least not harmful.
“If I had a world of my own, everything would be nonsense. Nothing would be what it is, because everything would be what it isn't. And contrary wise, what is, it wouldn't be. And what it wouldn't be, it would. You see?” -- Lewis Carroll, Alice's Adventures in Wonderland & Through the Looking-Glass