I'm a planner also --- some call it anal SW will open more fares on May 19th - I have an alarm set on my phone so that I can be ready to get my Dec 22/23 ticket.

I think the other airline prices will come down IF the fares are decent on SW. If your flight is over Thanksgiving then it's going to be pricey to fly. Try pricing out one way tickets. For Christmas last year, I flew SW for BWI to MBJ and my return was on United for MBJ to IAD. I saved about $250 on my ticket.

I use this site to check on prices: https://matrix.itasoftware.com

There's an App called Hopper that I've heard is decent. I am currently watching Dec 23 - Jan 2 and it's pricing at $1,037 (OMG) and it says until Oct 22, the prices will vary and can can drop as low as $747, then after Oct 23, price will rise by @$61 then by Dec 18 climb up to $381 more. Try your dates and see what happens.

I am more inclined to fly SW due to 2 free bags and if the fare drops, they give you the credit.