I think I’ve read all the relevant threads, but Hyatt is definitely a bit more complex than SPG, so I need to ask your guidance on what I’m missing…

Background: Heading to MCO and looking to try out Hyatt for a few stays while there. I’d like to stay in the I-Drive area, but I’m certainly willing to be flexible.

BWB promo – signed up for free nights, so that I can expand my property experiences.
Check certificates – the properties I’ve looked at only had single digit price differences (pre-tax!) between pre-paid and non-pre-paid rates, so not worth the effort for me to borrow my sister's Costco card, go get the certificates, etc. [Edit:] FYI, I don't have AAA, corp rates, etc.
Gx promos – I understand that if I choose a property with a promo that I shouldn’t mention it until check-in.
Points/miles - If I select a Gx promo, can this bonus be in miles? I thought I specified somewhere the choice of earning miles in my account, but I really can’t find it in my profile to change it. I was looking to get AA miles (since I’m not 100% sure how much I’ll be using Hyatt yet), but I could also take US, BA, CO or, if exceptional, DL miles...unless Hyatt pts are irresistible.

I’ll be following the advice of others and ultimately making 5 stays during other travels, then signing up for Fasttrack. Strategically speaking, could I get my 5 stays for Plat then, if I find I’m not travelling as much this year, just sign up for Fasttrack at the end of the year to maximize the the 180 days I have to achieve Diamond?

I know it’s a lot, so thank you in advance for everyone’s helpful, patient advice.