If I was in your shoes, I'd go with the iS101 over the iS111, particularly if your focus targets a 7.3 sail. With the iS133 you're set for very light winds, so I'm thinking that when you rig a 7.3 sail your goal will to be powered up, as opposed to milking the low limit of the sail.
One thing that remains somewhat of an unknown here are the water conditions you would expect to encounter at your locale using the 7.3. If the conditions can tend to be on the rougher side, I really think that the iS101 would clearly shine more and be more versatile overall. Also, you would have the option of easily dropping down in sail size into the mid 6 meter size should the wind really go off. Of course, it's unclear here about any other smaller boards that you might have that might potentially overlap with the iS101 or iS111. Still, all things considered, I believe that the iS101 is the ticket here.