I need help with the negative airflow in a new build.

Hello. I am currently planning on my first DIY PC build, as my 9 year old prebuilt is definitely starting to show the signs of it‘s age. For the case, I went with the Fractal North XL, as it fits my rooms aesthetic really well. Due to limited space, my workspace is also my bedroom, which is why it can get pretty dusty even with regular vacuuming. This being said, I obviously want to avoid a negative airflow to keep the insides of the case clean. However, if I mount the 360mm AIO radiator that I want to use as a top exhaust, it will end up negative with the 3 preinstalled 140mm intakes and the rear 140mm exhaust. So now I‘m wondering, what is the best solution? The radiator fans are Corsair RX120 btw.

The ideas I had were:

1. Remove the rear exhaust

2. Mount the top radiator as an intake

3. Adjust the fan curves so that the regular case fans always run with slightly higher RPM than the radiator fans

Do you think one of them is a good idea, or should I do it completely different? I‘d really appreciate some answers.