Open back headphones

Help me decide which one to get please! I'm going to buy a Fiio K5 pro as well so if you have any other suggestion for dac and amp feel free to help me. This are going to be for desktop use with my pc, I mainly play videogames (fps), listen to music, mostly from spotify at 320kbps but I have...

I just installed a new TP link ac1750 in my house but I need more range. I have a second TP link ac1750 that acts as a LAN in my office which is the current wifi dead spot. Can I just connect this with a cat6 cable and extend my range or will I need to config etc. Thanks, Kevin