Mags evolve at 10,35, and 50. With what you're looking at, you can actually get a rare mag at 5/50/45/0 with a blue, red, viridia, or white character... (I know you said you weren't looking at one, but they tend to grow faster... at least in my experience.) (I'm actually raising a savitri with those target stats right now, just have a female HU with one of those colors feed it to level 100.) As far as feeding goes, I'd feed it Antidotes until it hits 45 DEX, then Dimates (or monomates if Dimates raise DEF) the rest of the way.
EDIT: Just saw your current mag stats, I'd say feed it Antidotes until DEX is 44, feed dimates until POW is at 49, then give it to a female HU of the right color, then feed it to lvl 100. You'll have a Savitri and you can feed it dimates to lvl 200. If you don't want the rare mag, you can stick with Dimates the whole way, too.