There's not usually anything you'll wring from the airlines to achieve any discount on "bulk" flying to/from the same place, except for the eventual benefits that accrue from earning miles (I suppose if you cash in miles for an award ticket, you've reduced the overall per-flight price of the flights you take.). You should investigate whether a weekend round-trip to Charlotte is less expensive than a weekday round-trip to Orlando, though (benefit IME is not usually that great). Booking way in advance also helps, of course (depends on who's floating the cost of those way-in-advance bookings and how they're billed back).