15 marker:
No intro is required.
3 points with 1-2 examples per point (I'd use 2 to be safe)
If it's a to what extent question I do put in a little intro just to help me, but it won't gain you any marks. If it's a to what extent you also need to balance the answer, so points for either side.
45 marker:
You need an intro to lay out what you're talking about
3 points (there's no point trying to fit 4 points in, you'll run out of time)
People do essays differently, but per point I do: a paragraph in favour of my judgement, a paragraph countering that judgement, but they you need to counter that counter and return to your original judgement - do this in the same paragraph as your counter.
Per point I would use at least 5 examples, preferably 6.
Below I'll put my plans for both Unit 3c 15 and 45 markers, they lay out my structure.