The case comes with three front 120mm rgb intakes.
That is good.
I might add a single 120mm rear exit fan.
What cpu and gpu do you need to cool?
The case is a decent one for air cooling.
Do not worry much about motherboard fan headers.
You can normally use a splitter to manage two fans from each.
-Depends on what the hardware is.
-Which of the 2(cpu/gpu) you want to prioritize cooling for - can't win 'em both; optimizing cooling for one usually comes at the cost of a little worse for the other, with some exceptions.
I can only put 4 system fans in the case because my MSI B450 Gaming Plus motherboard only has 4 system fan connectors.
Phhtb. The H1 isn't that great. It's neat, but thermals are not so great. The aio leaves a lot to be desired.
The NR200 is a very good case, it should be, it's a slightly larger copy-cat of the Lian-Li/nCase M1. Whoever wrote that article is clueless about mITX cases. NCase, Sliger, Dan, Loque, most of those designs put the H1 to shame.