RE: acid or kombat
I'm not from the Starboard team, but I think you're on the right track with the Acid 74. If you chose the Kombat 87, your 6.0 sail would be at the very edge of board's recommended margin, whereas I'm sure that your current Kombat 95 handles it quite well.
Another option you might want to consider in place of the Acid 74 would be the Kombat 79. However, it's somewhat wider, and that could make a bit tougher in the highest wind ranges, especially considering your lighter weight. Overall, I think the Acid 74 would be your best choice.