Significant graphics lag on 2560 resolution: What are my options?

[narat]

Setup:

Dell D3100 DisplayLink USB 3.0 hub

-Dell XPS15 with GeForce GTX 1050
-ViewSonic 27" 2560x1440 resolution [Display Port cable]
-ViewSonic 24" 1920x1080 [HDMI cable]

Problem

There is an insane amount of lag. Graphics lag and mouse lag mostly. It's highly noticeable in everything from Excel to Photoshop. Graphics driver is up to date.

Questions:
(1) why is this happening? I have a 1050, there should be zero graphics lag
(2) any solutions?
(3) would a USB type-C docking station be better? Is the USB 3.0 my bottleneck for running the monitors off that?