Hey!
Well, I'd assess how well you're going to your other subjects. Even though SOR1 is a one unit subject out of 50, it still becomes a mark out of 100 (worth two units when it comes to HSC results) so if you do better in any other subject (that's not English) then SOR1 will count towards your 10 units, not the other subject. So I'd look at your performance versus your other non-English subjects. If you do better in SOR1, then you should definitely keep it! 
They don't do anything like that with SOR1 results, it's worth 1 unit

But it will count over half of other non-English subjects if you do better in SOR than one of those!
If you were starting Year 12 I'd say drop for sure, given you hate it. But given that you are already halfway through the year and doing well in SOR, it might be worth keeping as a security blanket? It's always nice to have that peace of mind

It's ultimately your call - But in my view, you've invested at least
some time in SOR already and it seems to be paying off. So, to make that time worth it and give yourself some peace of mind, it could be worth keeping

there's no right wrong, just my opinion!