Definitely dont pasteurize it - that will set the pectin and it wont get clear.
If the juice is fresh, hasnt been sitting around, and was pressed under sanitary conditions, dont add k-meta/campden. You will get more apple taste and be able to drink it sooner. If any doubts about the condition of the juice, use half the recommended dose.
I'd recommend using an ale yeast and cold crashing to taste - usually somewhere between 1.004 and 1.012