Does Blu-ray (HDMI) give Roku better audio & visual?

I’m not sure I understand the question.  Blu Ray Players, Cable Boxes, Games, Streaming devices, etc. all connect to TVs via cables - usually HDMI.  The other option for some of those is component video cables, but component AV takes 5 cables instead of 1, so I don’t see how that would help you.

When you wall mount, you certainly should think about cables and connectors, both now, and when adding devices in the future.