Need assistance for optimal fan setup for Asus GD30

[Xem]

Good afternoon, everyone.

I've been looking to install some extra fan in this pre-built (Asus Desktop GD30), but I'm unsure as to how and I was wondering if someone with more knowledge would mind helping.
Here's the current fan setup. (No fans on the front and no side exhaust/intake)
Only one fan on the CPU and a 120mm for exhaust in the back.

https://imgur.com/mxVHHe2

The airflow comes from the front (and top?) and is exhausted from the back. While this works enough to keep my CPU and GPU somewhat cool at max load, (Max CPU: 72C and GPU 78C) these temps still kind of bother me. GPU is GTX 1070 Blower and my CPU is I7-7700 3.6Hz

I'd like to install 3 120mm fans and a 92mm fan. One 120mm in the front to increase air intake, 2 120mm on the top to either exhaust or intake? (Not sure which way would be best), and one 92mm on the bottom left for exhaust.

Does that seem like the best way to proceed? I'm also wondering if increased air flow under the GPU from front to back would prevent the GPU to suck enough air to be sufficiently cool.

Thank you very much for reading!
Best regards, Emile

 

[Xem]

Any help would be very much appreciated =-)

 

[Aeacus]

Since hot air rises, case's airflow rule of thumb is: front & bottom - intake; top & rear - exhaust.

As far as side fans go, those are iffy. Though, i've mounted those as intakes to bring more direct cool air in for GPU/CPU. It especially helps when your have top-down CPU cooler. With tower CPU coolers, side intake isn't as beneficial.