happily hopeless child
1 - plan your arguments beforehand, thats one of the biggest time killers. give yourself a minute or two to plan 3 good arguments based on the prompt and evidence provided and it makes structuring the rest of the text really easy. also use a paragraph structure like PEEL or TEEL or whatever, it'll help you cut down even more time.
2 - pretty sure inclusive language like "we" or "you" is fine, just refrain from using pronouns like "I" or "me." at the end of the day its up to you idk if it really makes a difference
3 - definitely not, i would assume they are both taken into account equally
4 - depends on what ur second piece is, if it was persuasive and u didnt finish most likely but if it was creative u could simply end on a cliffhanger, probably would still lose some marks tho