ajcollins80 - I have a EK-DDC 3.2 in my S2.0 and it does not sit in front of the RAD/Fans, but to the side. You get a small area between the RAD, case window and end of GPU to place the vertical pump/res combo which works well.
The issue with the S2.0 is the width of the RADS. I currently have 40mm EKWB PE and while it works, it is tight. I would recommend the 30mm SE to give you more room to work with. I do not believe the width effects performance that much.
I use 13/10mm flex tube and fittings as I prefer the look of the smaller tubes. Because the case is MATX, the tube runs are small, so you get no issues with bends