Low-end GPUs are a very poor value proposition. For $89 you could have an RX 460 with nearly 3x the performance of the R7 250 plus HDMI 2.0b and DisplayPort 1.4.
What is the added value of 5 times more than enough compared to 2 times more than enough?
The R7 250 is considerably less than enough if you have a 4k monitor. GPUs aren't just for gaming - if you use Photoshop or Premiere, you'll want a decent GPU. An increasing number of applications are making use of GPGPU processing.