Suggestions enhancing airflow / lowering fan noise Probook 430 G1

Hello I'm new here. (i've been fixing and breaking things for couple of years now, short intro)

I bought a probook 430 g1 and it's fan noise is not extremely loud but very annoying nonetheless.

I was looking at the tear-down for possibilities, the thing that strikes me is the air-intake below the keyboard.
Not only does this design make more noise compared to the bottom, it would also suck in spills of fluid.
Also i don't know how tight the keyboard sits on the air-intake but on the bottom it would be able to suck air in more easy i would think, maybe with raised knobs on the bottom. So that would be a thing to try, if not do tell.

The other thing i noticed were the cooling-ribs where the air is being blown through, they look so tight, would drilling some small holes (which is hard to do nicely) help or worsen the cooling? Or cut out some ribs, like leave one, cut one, leave one, cut one, and so on.

And one other thing i just wondered is if u take off every other one blade of a fan like that would the whining noise be less and would it have a big impact on how much air is being pushed?

(I've already lowered noise by 50% with fan-control software only heating the cpu 2 degrees Celsius more, but these things above keep lingering in my mind)