I wouldn't touch K&N. The filters get better as they get dirtier. I had a buddy that built a box with a vacuum under it with a screen. He set a cotton ball between the screen and the filter. Turned on the vacuum with the K&n filter mounted to it. It was my filter from my truck had about 6 months of use on it. We mounted the filter and sprinkled some light dirt over it. I thought for sure the filter will perform. The cotton ball was brown. 80% of the reason your oil is dirty is from the filter. I have the air intake kit on my chevy, I've since swapped out the filter for Amsoils filter mounted to the tube. Did the same test after 6 months of use the cotton swab was still white. K&n aren't that good
Can’t flow more air unless you let more air in. For a given size filter the only way is to not filter it as much and let it bypass. Thus the reason for the dirt getting by the filter. They make a prefilter wrap to put on them. I remember in my jeeping days in the early 2000’s guys were running the k&ns with a foam vacuum cleaner filter tied on the outside. the consensus was paper is better for off-road and if you wanted to run a K&N best to stay on the road/drag strip. Shortly after that k&n offered it from them as an accessory. Any filter that needs a prefilter to work properly is not a good filter.
I run a Amsoil cone filter, it fit directly to the K&N intake tube. It's synthetic nanofiber technology. It's a 100k filter that's cleaned with air not oil. So it 99% from out of box or with every cleaning. https://www.amsoil.com/p/eaau/