Hey Hydroxyl, (lovin the name btw

)
Chiming in with everyone else, I'd definitely say that you should prioritise your 3/4s (two 3/4s too! So impressive

), but also don't neglect your 1/2s completely (especially English

, as it requires building up writing skills. I probs should have worked harder in Eng last year

). I'm probably not a good example, but last year I didn't really understand the importance of my 3/4; crammed for SACs the nights before, and only starting revision for exam at the end of September XD (<<--- don't do this)
What you should do is to list out all the tasks you need to do at the moment, and sort them by
urgency and importance. When there's multiple tasks to be done, ask yourself, is it urgent and important? Prioritise the urgent and important tasks first (like studying for an upcoming SAC), then proceed to do the urgent but not that important (like upcoming unit test/textbook questions due, etc). It's good to also allocate some time each day to do tasks that are important but now urgent (like starting revision for end of year exam, like doing practice exams for bio and further

. Making a study timetable really helps with categorising the tasks, doesn't work for everyone I know, but I find it helpful to make a study timetable and be able to put all the stuff I need to down

There's also this cool to do list thing where you can prioritise tasks by importance/urgency called Habitica

{It's in my signature if you wanna have a go at it}
And just like Swag said, if you're cruising in your 3/4s then you don't have to feel pressured (or guilty) to keep working at them.

on a side note: lol I probably use way too much smileys