A single 140mm intake in the front would likely be enough considering the cpu is cooled with an aio. If the aio cooler is exhausting out of the case those fans will also be evacuating some of the warm air from components. 2 140mm fans as intakes should be more than enough.
I have a similar setup though my gpu is hotter than the one in your build. I'm using the enthoo pro so using the stock 200mm intake that came with it as my only intake fan and my system stays plenty cool even with the cpu oc'd to 4.6ghz and an air cooler. My ambient temps range from 22c to 26c and no issues when gaming under load.
If looking to add a couple of 140mm fans I'd consider a couple more phanteks fans. Just pay attention to the model numbers, some are 3pin...