There is very little correlation between how many superiors you get and how well you do in VCE unless at maybe 99.6+ . VCE is pretty much specifically designed to award hard work over talent. I only got 2 superiors and didn't get into Melb High (my brother did with more superiors) and ended up with a 99.25. My brother had all the same opportunities as me in VCE and did the same subjects etc,, but went to Melb High and didn't break 98 atar. He did however, do far better than me on the UMAT. Therefore, your superiors will not affect your ATAR as much as you think (or at all)
Workload, of course, depends on how well you want to do.
Melbourne High places a strong emphasis on clubs and extracurricular activities (hence the motto they publish on the website is 'more than just marks' as opposed to the motto they traditionally employed 'honour the work'). You will be given the opportunity to join plenty of clubs of types that you would never have experienced in your old school.
You will be given plenty of opportunities to meet MacRob. Since I don't go there I can't list all the separate opportunities you will be able to do so.
Unfortunately a lot of students at Melbourne High are displeased at their teachers. There are quite a few who refuse to put in the effort (note: zhen), and many as such, get tutors. However, tutors in my experience mainly only help by providing the motivation for you to get through a grueling VCE year by making sure you don't fall behind. There are plenty of notes and resources out there that if you utilise, you will not be at a significant disadvantage compared to your peers. In fact, I heard of a story of some migrant learning English in 2 years and completing vce with 99.90 atar with no tutoring. Therefore, everything is out for there to achieve. You just need to maintain your motivation, which is easier said than done

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