It won't help. One reason why the Queen Elizabeth class has two islands is because the two gas turbines each needs an island to house the enormous exhaust. On American conventional carriers, the island is small but is sufficient to houses both intakes and exhausts require for all boilers.
This isn't an option unless the carrier is nuclear powered. The island houses the exhaust, and the exhaust must sit on top of the boilers. The boiler room is placed amid ship, with turbines placed immediately in front and aft of the boiler room, so as to reduce the amount of plumbings. So, there is no choice but to place the island amid ship as well.