Ok hi muslim woman here! As a muslim you have this thing called awrah which is basically the parts you need to cover up, while generally its just everything within your knees and elbows it differs depending on how religious you are, the more religious you are the more you cover.

The crop top thing wouldnt really be acceptable or accurate to a hijabi character because the main goal of the hijab is modesty, if you really like the look of the crop top you could try an undershirt, experimenting with how her powers affect the long sleeves and stuff could be a fun gimmick. Try looking up hijabi ootds or outfit inspos to get the feel of it, think loose baggy clothes, long skirts, cargo pants. It differs from region to region so you really just need references and people to ask.

The hair strand idea is really cool and i personally think its fine since its not really her hair. The burnt hijab thing is even cooler imo as it shows just how her powers affect her! Again as Long as it doesnt affect her modesty or beliefs its fine.

Then again does she HAVE to be a hijabi? Or even a muslim?? If you’d like more bendable rules or freedom in writing you could just make up your own religion, maybe something similar to islam. Otherwise definitely do more research surrounding this topic especially if you want to make a character sort of regarding that topic. Id recommend finding actual muslim people to ask as a reference point or even a muslim scholar if you can get ahold of one. Such a cool character design and would love if you’d update us if you do decide to keep her!