We all know whatever your kid gets, he's going to go play online and kick my ass like the rest of those jerks do.
As for controller preferences, just buy the controller you want and a
CronusMax from Best Buy. I used Xbox 360 controllers on my PS3 with it, and it works with X1/PS4 now. You need a 1:1 controller ratio, so if you had a PS4 and wanted to use two Xbox One controllers, you need two CronusMax units and two PS4 controllers. But if you really like the controllers on one system but the other system itself, you have options.