Increase the processor core count (fpr example 6+ on 1 socket) of the guest vm and the system memory (6gb+). Then increase the VM's video memory, try 4GB. You will need a lot of memory and raw CPU-Power to run 4k/32bit in a virtual environment (or reduce resolution/color depth). One of your virtual 2d-frames will use 15.6Mbytes of memory (2560*1600*32bit), which has to be moved from your physical ram to your gpu - what does not happen in phy environments. That happens at the cost of Ram, Cache CPU and PCIe.

On my Machine, for example, I use 4K resolution at 3840x2160x32bit(~8.2mp) = 31.6MB. On Phy this takes 240kbyte of memory (because most pixels are done in vram), in VMware Workstation I can see 35Mbyte (of native ram).

A single frame buffer therefore requires more than 32MB to display a 4K image. That thing moving around is causing the delay.

The problem is going to be, how much hardware you can throw on it without any accelerators. Which is the culprit in this case, because video accelerators don't work with VMware Workstation, except native 3d stuff (Settings> Display> Accelerate 3D). CPU-Integrated graphics are limited by their nature and adding a larger card is going to give you a increase in 4k speeds.

Additionally, mobile gpus like in this case are significantly slower than the powerful desktop brotherhood. That may cause some of your delay, too.

In my case, I can run a vm on my desktop (2x Xeon E3-1245) nearly fluent, but on my Notebook (some i7m stuff, same ram, same ssd) it's super sluggish.