meh. I kinda find the normal isekai kinda magic boring, im more into mysticism. But rather than talent, i prefer thinking it as affinity for certain elements if its elemental type magic, or better ways of usage if its of another. For example taking a spell and just applying it differently to create different effects, or making it more efficient.
Ever since reading Wheel of Time I think of ideally magic should be thought of as "weaving" and a spell as a "tied off weave" Like knitting. You start knitting and tie up the loose ends, then its done. Thus when its magic the "weave" becomes a spell. Some people are better at weaving than others, creating more intricate and larger weaved. And some have higher affinities with certain elements, a better understanding of the element, and combine it with others and control(weave) it to a degree where you have these awesome spells. A min-max effect if you will.
I find a practical approach is rather neat too. Like fireballs. Lob one at a person and it wouldnt even hurt. Wht? cuz fire itself is intangible. It wouldnt hurt you. The HEAT hurts you. Now look at a ice spike. Its tangible and sharp, so itll cut you up real good. The cold effect would be secondary. Thats a common sense sort of thing. A lot of times fire is considered OP in destruction, when really, there's a limit to how hot it can burn naturally. So you would have to use it in other ways or figure out how to make it hotter.
When it comes to elemental magics i always look to Avatar TLA for examples, they pull it off magnificently.
And the dude above made another good point, resistance to your own powers. You shouldnt be automatically immune to lightning or thunder or fire and heat just cuz you can use it. You should build up resistance to it so you can bear its power, and that could also be another factor in combat. Who can resist the opponent;s attacks better?
Im planning to introduce all those aspects into magic when i get around to writting it in. I want a solid foundation instead of writting, "cuz magic"
A bit of mysticism, critical thinking in usage of magic spells, and practicality in combat spells. I hate when writers just say "its a simple spell but because this guy has such huge reserves of mana pumping into it, the spell is twenty times more powerful than a nornal person;s would be!"
As if nothing matters except how much mana you have, which is fucking bullshit in my book. Nah, you get by on skill or sit the fuck down.