I have been traveling 2-3 times a year during peak times. I think in the ball park of 200.00 is a great price for your family.
You might want to wait for SW ding or Jet blue for lower prices, but it is like Russian roulette. My opinion, book it, have peace of mind, & start obsession with your trip.
In the past 3 years or so, all our airline tickets, regardless of airline, for IND-MCO-IND have been between $180-200. I think that's what you can expect to pay. I'd book it, in case it goes up.
Used to be able to fly cheaper, back when ATA was based here, but things have changed.
I fly out of IND 10 to 15 times per year. Two or three of those trips are to MCO. I would wait until the SWA fares come out for your period of travel. When that happens, NWA and AirTran should lower their rates. I just returned from WDW (Jan. 28-Feb 2) and paid $117 r/t on NWA which included all fees and taxes. I made these reservations on Dec. 14th. which is 6 or 7 weeks before the trip. The time period you are traveling is a slower period and the fares should be good.
I don't expect to get the r/t cost from IND to MCO as low as $117 each time, but I think you should get it for $150 or less. Keep checking the fares every couple of days and I believe you will do better than what you have now. Also if you are flexible a day two can make a difference in cost.
I'd wait. We flew Southwest from Buffalo to Orlando this past September for $100 roundtrip, total, per person. it was a Ding and I just kept booking and rebooking while fares went down.
September is a slow time to travel to Florida, so my guess is those fares will start going down.