Hey there! I'm going to be upgrading my monitor within the next few weeks along with my gpu and I honestly have no idea which resolution would be ideal. My current options are UW 1080p at 29 inches, 1080p144hz (with FreeSync) at 24 inches, 1440p at 25 inches and 4K at 27 inches. If I were to get the 4K monitor, I'd more than likely play at 1080p or 1440p so I can still play at higher settings with 60fps. I play mostly open world games with the occasional FPS with friends, though I mostly play casually. My new gpu will more than likely be an RX 580 unless there's a decent sale for the 1070.