General survivability seems like a good fallback? Like, if we think we're going to get attacked by a witch in the next few hours and can't come up with better utility, we do that.
Alivaril even suggested wishing to become the strongest magical girl that our potential allows, as like, the generic template. So something based on that, or maybe that but focused on protecting our friends?
alright, well what is there that Mtg magic can't actually do? I'm kinda drawing a blank, although that may be because I'm used to thinking on a planeswalker's powerscale rather than that of a normal mage...
This is sort of rough, but generally...
Mind control is possible, but it's usually absolutes. You enchant a creature and get to take it, or you get to force it to fall asleep or attack as an instant spell. Nothing subtler or about controlling emotions is common. (You could say that the field wide buffs like anthems are a morale thing and might be emotion affecting but that's borderline.)
Teleporting is pretty rare. Not like, impossible, but most things to do that are going invisible/phasing through walls, or flying. Long ranged transport is a planeswalker staple, hence them being able to pull creatures across planes in the oldwalker days and still being able to Walk, but very few other people get it.
True, large scale resurrection is rare. Canon mage level necromancers work really hard at each zombie, while a planeswalker equivalent gets to bring everyone who died in a given city or region back to life to make an army. Unless you're an angel or a god, actual resurrection is pretty much off the table, and even with Angels it's a rare effect.
For burn it's the same kind of scale as necromancy. You can shoot fireballs (well, not the actual Fireball but little ones, you know what I mean) but you're not throwing around city destroying meteors without a lot of time investment before hand. The same goes for boardwipes, which are on one really powerful
magus, and one plane destroying
baby god.
When a small scale mage summons things, they're tokens. Tokens, generally speaking, can't be ressed or brought back from exile, and dissipate in reaction to bounce spells or other things. They're also smaller and almost always vanilla (no abilities, just have power and toughness). So we might be able to summon little spark elementals, or goblins, but they'll be of the generic type almost certainly. Still have Puella Magi stuff beat, though, discounting familiars.
Alivaril might scale things up so we get actual creature summons, but those are like, the defining trait of a planeswalker from most of the fluff. I'm betting if we do it'll be expensive.