Sorry, I don't fully understand what you said. I'm a simple, plug and play sort of person at heart. I know headless means no screen - had to look that one up the other day! But I gather you mean that you use your mini PC as a media server and file storage device.I just access mine headless from my main gaming PC, laptop or work (or even smartphone) 99.99% of the time just using OpenVPN & RDS so normally no screen/keyboard/mouse use to it. Just used as a box for file storage & as media server using as little power as possible with it on 24/7. Can be sat untouched for months just doing its stuff with occasional updates & new files transferred to it.
Will longer antennas be better? I already have these,
They look longer than these,
I think I might as well get the above the set you linked me and I can compare both.