keziah
Hey keziah,
I haven't been here in a while, so just to re-introduce myself: I'm @PhytoPlanktonkton, and I graduated in 2021 QCE.
Subject changes are usually very tough decisions to make. If you enjoy maths and are somewhat good at it, I would recommend specialist maths. It scales very high (good for your ATAR), gives you adjustment factors to certain unis and degrees and helps with some prerequisites to some degrees too.
However, if you are proven to get exceptional grades in psych without much work, it obviously can be considered your "chill subject" (a subject you can pretty much ace without much work). I would go down this path if you have another five subjects that can back you up just in case because if psych goes down then that will pull you down a lot if you don't have a backup.
This is what I would recommend: take a look at the QCAA syllabuses (unit 1-4) for both psychology and specialist maths. If you find both of them interesting and you think you can exceed somewhat in both then specialist maths is definitely the way to go. Also, check the scaling report of last year too - it will give you an update on the relative scaling of each subject.
Anyways, that's what I think but let me know if you have any other questions.
Hope it helps.