Some people who do all the maths and science say specialist requires most study (meth, spesh, physics, chem)
Yeah I did all of them and I agree that I studied most for spesh out of all of them. But some notes:
- studying that much for spesh and doing methods in the same year meant that I really didn't have to put much time into methods. Apart from probability, most of it was almost assumed knowledge in spesh.
- finishing the course early and focussing on
understanding everything and having a good teacher meant that most of the study was just finding tougher questions to try and doing trial exams.
- again if it was further a larger amount of time would have been spent trying to find out how to stop making careless errors, which is far more time consuming and difficult imo

But that's just my experience.
The question you have to ask yourself is 'am I good at maths?' Obviously the question is very subjective, so rephrase it to be 'am I finding methods fairly straightforward?' If so, then spesh is a good option to get a high SS after scaling. In addition you will be taking a subject that is quite interesting. If methods is being a bit challenging then maybe you should just go further. The reason is that if you are good at maths and find methods straightforward then you probably will eventually (you've got a year) understand all of the concepts in specialist maths. Depending on your aims you could then begin looking at 40+ which scales to 48+. If you do further when you are a spesh-capable student then you may aim for 48+, but that'll just come down to your luck and concentration on the day of the exam.