IMHO understanding the Hamlet character is the most important aspect of the critical study. The play's genre and 5 act structure are inter-related (it is structured that way because it is a revenge tragedy) but it will be difficult to write an essay of huge substance based on the fact that the play follows an exposition, anticipation, confrontation, delay, and finally resolution structure, and that Hamlet is important in each scene - after all, he is the protagonist so obviously he'd be important. It is more imperative to understand
why Hamlet chooses to do the things he does, and how those choices impact on the structure/reflect the genre and how these choices also resonate with the audiences of time.
Remember the Hamlet question will always ask you what your opinion of the play is, so really it's up to you what you want to write in your essay. You can freely argue against the question - I did in my trials and external HSC and got 19 for both essays - but you need to be
very informed and able to understand the perception of the question too. It is unlikely the structure of the play is going to play a vital part of the question; it will more likely ask about values and paradigms in the play that might resonate with you, or certain important aspects of the play and your opinion on them such as characters. But again, the question is open for dispute and it is up to you to decide how you are deciphering the question. For example, last year's question;
"An inherent tension between confrontation and resolution is revealed through characterisation in Shakespeare’s Hamlet.
To what extent does your interpretation of Hamlet align with this view?"
you can interpret in a number of ways. Some people in my grade thought that it was referring to the specifically Acts 3 and 5, while others like myself took the literal interpretation of the question purely asking about whether the confrontations in Hamlet as a play led to, and were, satisfactorily resolved. I hold the opinion that Hamlet has an irresolution but
not through characterisation, rather through the inconsistencies and contradictions in Hamlet's choices, quotes, and actions as the play comes to the end, and this is what I argued in my essay, explicitly stating that characterisation was minimal to my understand of confrontation and resolution in each of my statement sentences and concluding paragraph sentences. This suggests boundaries forced onto Shakespeare from his audience, but I won't go into detail regarding that just now.
Reading critics' perspectives of Hamlet may be helpful too, particularly if you discuss Hamlet in detail. The BoS want insightful perceptions on the play rather than generic "here are 3 themes and that is why Hamlet is good" responses. If you want to talk about the structure of the play, there are some interesting observations by critics that Hamlet's language use changes as he interacts with specific characters and what this suggests about himself and the other characters, e.g. he talks in iambic pentameter when speaking to royalty, however, he speaks in prose in his monologues and when talking to friends he thinks are loyal. Does this suggest that when he speaks in iambic pentameter he is actively trying to conceal something from other characters, and also hint towards his own view of who is loyal or not? If that is the case, then certain lines can hold incredibly different meanings to what he is actually saying then.
Sorry for the ramble but I loved Hamlet and it is by far the most diverse English text to study
Why year 12 students are stuck trying to decipher a text 400 years of genius critics are still trying to decipher is beyond me, but it's still remarkably fun to try.
tl;dr Hamlet is deep and you are better off finding one perception of the play you strongly agree with and arguing that regardless of the question. Don't focus too much on the structure of the play, sneak it in a line in each paragraph, but the bulk of your response needs to logically reflect how you came to your understanding.
