AZ –
They either wait longer till they start going out (there are plenty of people who I know that waited a good few years till they were 26,27,28) to “find themselves” but they take themselves “off the market” or they marry “not” good girls from more modern families – but those families aren’t on your radar of shidduchim – so it doesn’t make a difference to you that a more modern girl gets engaged – she wasn’t on any of your lists
On your island you would have 25 boys go off the derech and walk to the other end of the island and marry the Indians while only 3 girls did that. Then you would have 147 girls to 75 boys. (and why are you starting it at 150 and 100 – the numbers aren’t that messed up – there are plenty of single boys out there)
And by the way you seem to have completely ignored my first point.