>>14930127>she should be venting heat to her surroundingsYou are missing one very important point: Cirno might be the strongest, but she's still a baka; her power might be almost entirely subconscious or instinctive for all we know. And with that might come lack of full knowledge about it.
I can also see how her power would be unidirectional, not physically able to vent heat, only to absorb it and slowly let it die out. Otherwise she should be a temperature fairy instead of "just" an ice one.
>excessive use of her own power should begin to cause her to meltThat is only if you assume there is no limiting factor to her power, she might not be able to cross the line herself, it's a logical self-preservation mechanism to have. In any case, I think there are multiple ways of explaining that alleged discrepancy away that are consistent with my theory.
All in all, I think relegating the explanation to more or less "it's magic, so anything goes" is a simplistic way of analysing the greatest fairy.
