Definitely highlight how unequal it is. I definitely think a good starting point is making her understand this.

She cannot judge your comfort based on her own when it comes to heat. Anything else is arguable - this isn't. You get so much hotter than her, end of. And it's severely unfair to be forced to be so hot all the time (as I remember, from my obese days). It greatly effects your health and wellbeing. 

My boyfriend will be sleeping in nothing but boxers and one leg out from under the duvet,  whilst I will have full fluffy PJs, plus an extra hoodie, plus an extra blanket around my shoulders, fully under the duvet. The temperature difference and comfort levels with temperature is huge. Even if your personal differences are less than that, that's still big.

The point is though, we colder ones have the option of extra clothes, which are quite cheap. You hotter ones can't really do much if the environment is too hot... your only option is make it cooler... clothes that make you cooler exist, but are freaking expensive ofc compared to a fluffy jumper.

That's enough for me to believe that you take priority with environment temperature.

Plus, you can snuggle her to warm her up :3 I snuggle up to my SO when I am too cold, but he is all warm like a hot water bottle &lt;3

It's sad that she isn't taking you at your first word that you are uncomfortably too hot, but it can still be fixed. Sometimes people do need extra explaining.

If she doesn't care after you make her understand this (can even do some google searching to show her its an actual thing, at a stretch) then you have bigger problems - mainly, that she really doesn't give a shit about your wellbeing.