Summertime drying and curing takes patience. Slow and low, keep the room at 60/60 or bite the bullet and get a controlled dry/cure box like a Cannatrol if temps keep fluctuating. As for inside the tent, may need a bigger ac unit to keep those temps steady.
Gaia Green is basically like all the DTE nutrients mixed into one, like a super soil without the soil. It's a dry amendment that work great but take up to 2 weeks for it to breakdown for plants to use. On top of that, you have to top dress every month or so. I'll stick with my NTFG. As mentioned, you don't need every bottle in the line to have a successful grow. You gotta figure out what it is you want to achieve while growing, some want more yields/density, others want more terps, and everyone wants both lol. Find your medium and start there and once you're established and see the results you wanted, then add more of the line and see what it could do for you, your plants and your growing goals. Every nute line is perfect when dialed in and used accordingly, it's just a matter of opinion and budget that separates us on which nute line is "the best" for cannabis.