"A great tactician creates plans.
A good tactician recognizes the soundness of a plan presented to him.
A fair tactician must see the plan succeed before offering approval.
Those with no tactical ability at all may never understand or accept the plan.
Nor will such people understand or accept the tactician.
And when a mind is too deficient in understanding, the resulting gap is often filled with resentment."
Magicians have always been hard to place in the hero hierarchy.
I'd say that for whatever reasons (some in comics and some out) magic power is more variable and dynamic.
Yes, certain types of magicians can often benefit from prep much like scientist heroes, but in both cases prep is often overrated. We think too much of the cases where an Iron Man or Mr. Fantastic does some uber prep, but not enough where they either failed or more often didn't even try to do the uber prep despite having time.
At any rate, Doctor Strange or Doctor Fate are definitely elite top tier heroes. Sometimes they are more; sometimes they get dealt with more easily.
A lot of where a magic user is placed in the power spectrum depends on how their powers function. Some magic users require rituals or incantations. Constantine for example with some of his needs to do certain movements or draw a symhol like a pentogram light candles. Others like Zatanna need to say words in a certain way. Then you have yhe likes of the afore mentioned Drs Strange and Fate who simply need to visualise or think of the desired outcome. Naturally this makes them more dangerous as they can do more much quicker.
I liked the way DC had it set up pre flashpoint (not surenif it still stands that way). Basically for mortals to perform magic usually required ritual or incantation so that the magic was controlled outside the body. This was because using it within could tear a mortal apart. If you had talismans you could do it through these and as such do more with less (as they were made to wield it). If you were immortal more again (hense why PS, Spec, Zor and the likes of Nabu and Mordru are so powerful.
I kiked it because it gave a framework of why some needed ritual and spells an others didnt. The others could still use spells (to perform even stronger magic than they could with visualisation) of course.
Thats why Fate could just think or point and make ankh vlasts or shields or create constructs (as we saw his wife Inza do often when she was Fate) while Zee needs to say her backwards words.