Children in rural areas probably won't be in any different a situation, because they will still have to travel to a sixth form that acts as a hub for the whole area.
This brings the possibility that there might be more sixth forms, thus giving them more choice.
Minimum of 200 expected pupils isn't that big, and shows they have been listening to some of the (vocal) criticisms of free schools not having to meet a particular level of demand. So this part shows that places must correlate to requirement.
15 subjects seems OK to me too.
I'm a bit wary if the stats over the time frame chosen for this article, because it straddles the raising of the participation age, and comes just before the years when the demographic bulge will rise to 6th form age.
Again, the voices about the shortage of primary, and now heading into secondary, places included 'why didn't they see this coming and plan ahead?' Well, creating places just before anticipated need (which is what the article appears to describe) is what that sort of planning and prior creation would look like.