Not *board team, but here is what I think (I've sailed several iSonics and have 3 mates who are around 95 kg - all freshwater iS sailors).
If you go for 2 slaloms, you can go smaller, especially for the smaller board. iS117 (75wide) is not going to be any fun in Force 7, no matter how heavy are you. You should look at the 107 and even 97 models depending on how steady is the wind. You'll have no problem with 97 in steady force 6. From my experience (and my heavyweight mates'), iS137w85 is big enough for all lightwind duties, but I haven't sailed a slalom as wide as iS147w93 so I can't comment. And I'm not sure iS137 can carry a 10.7. If you have a lot of 10kt days you'll be better off with a Formula anyway.
So you need to estimate your wind conditions realistically and go from there.