According to me, all of the proposed boards in the responses so far will work fine.
The question is, what will work the best for you.
If you would have asked me for a 8-12 wind range, I definitely would have said the US but with a 10+ sail.
For a solid 9-15 knots, perhaps you're better off with a smaller size. But always remember that in light winds, sudden lulls can and will stop you from planing when you're on too small boards, especially when you need to point to come back to your starting point. If you don't mind this go for the smaller size. If you hate this, like I do, go for the bigger size.
I'm 87 kg and recently the proud owner of a US147 and I can tell you that this board is really great in ultra light winds starting from 8 knots. On the other hand, it also behaves very well when the wind picks up even over 15 knots. I also use the US when I'm with my IS122 + 8.8 sail in 15 knots and suddenly the wind gets unstable. I only change the board then, not the sail, so US + 8.8 and boy this combination rocks !
IS87 / IS101 / RRD114 / US147