C7100V issues!

I am the proud owner of the C7100v... but with 30+ devices - the wifi sucks! I show the best case at 40% wifi connection in a 2 store Condo of 1200SQF.

The router is located upstairs and even there the best is 60% - was wondering do I need a better WIFI Router to get better results... and if so what would be some awesome suggestions. I do not do gaming... but I do have Echo, Ring and Netflix, Hulu streaming... Thank you for you time and most of all thank you for your help; looking forward to hearing some recommendation!