Hey there Mj, hope you dont mind if i tag along for the ride.
After reading your journal so far, im using the same LED company 900w version, also im using fox farms soil(happy frog tho) mixed with extra perlite (45-55 ratio) the difference ive learned with FFHF and FFOF. Is that the Happy frog is easier on seedlings and starting veg and then the soil starts losing nutes after that in the soil. Thats when you start adding your nutes. Witch your plants will tell you when they need it. Now with OF type. It tends to run Hot. Any younger plant you need to be careful. But for a older plant its really great stuff. Has alot of micro biological going on in it. All in all the soil you have will be fine. Just give the plants time before you give any nutes. Just water them as needed. They will tell you what they need
My humidity for my tents are between 40-50 lights on and then Jumps up to 60-80 at night. Id learned that plants do grow better with optimal humidity but they will learn to adapt to what they are surrounded with. Honestly 40-50 humidity is going to be perfect for bloom.
But enough of my talking. I look forward to seeing how your plants do!! Keep up the good work and i wish you all the luck!
Goodluck!!
EDIT
If you have any questions feel free to ask ill do my best to answer them as well as everyone else im sure