To OP,
Yes on both counts. The grilles on my old Enlight case were very open and actually convex so that the air didn't even hit it until it was already dispersing. But I imagine it costs quite a bit to add something like that to the tooling - it might have required a whole extra tool and die and another stamping station. Too expensive to waste on cases today. I don't know why they just don't stamp the holes out entirely and toss in a couple of those wire grilles. Naah, that's too easy...
Here's a test you can do at home: Try to lip-whistle (as opposed to the tongue and fingers method) with your mouth wide open. Now try it with your lips closer together. I can whistle both on the intake and exhaust that way...
To theman,
. Don't cut or remove those - my Berserker has similar. They are well away from the face of the fan so the air is dispersed at that point, and I'm sure there are other vents for the air to come in as well such as at the bottom, top or sides.
.bh.