You should have read my Project Log lawl.
First up, the AX1200 with fan issue. I have the bottom fan installed, and I can easily see about 5cm gap. The AX1200 is 4cm longer than the AX850, which is what i have in my system. I also have a 140mm fan in the bottom, so you will easily fit your fan in.
Next, the 200mm fits easy, or mine does. I have the CoolerMaster MegaFlow Blue 200mm, it fits perfectly.
I have 1x 140mm exhaust, 2x 140mm top fans (you have to fit them in cleverly though), 1x 140mm bottom fan, 1x 200mm front fan.
All the 140mm fans are Noctua NF-P14 FLX.
Also, I've attached the bottom fan using spare motherboard standoffs.
And my case has the same space as yours, you just have the cool lighting side panel