Alright, pretty satisfied with how I've got this set up now.
I'll head out Thursday so that I won't be scrambling for Friday night gamepak, and will have most of Thursday to relax at the pool. Went with THEhotel given the season and primary plans to poolpak. First booked the Saturday night that was 2-3 times as expensive as all the other nights with Hyatt points. The 22,000 didn't similarly increase for the Saturday night vs. other nights. Then after trying a few different ways that you'd think wouldn't matter, got the cheapest rate booking Thursday and Friday nights through MLife. So I've got the first 2 nights there for a total of $304, and then Saturday night for 22K Hyatt points.
I'll be giving my Southwest and Hyatt program info at checkin and getting points to both of those for the stay. No bonus Hyatt credit card points for staying at a somewhat-Hyatt-but-really-MLife-hotel so using Sapphire to pay for that.
Will also get my MLife Gold card upon getting to MB and showing my Hyatt platinum card, and that should help with things during the trip.
Only thing I let myself down on is that at the outset of working on this tonight, changing my Friday flight to Thursday would've got me a $90 credit back. After however long it took me messing with all that, the Thursday flight had gone up so I only got a $45 credit back.
If there's still pak'n to be done come noon on Sunday, so be it, I'll change flights and get another room and go back Monday. Going home after 3 nights there and having a day to recuperate sounds good, tho.