Going back off track...
Have an iMac and MacBook Air, no mini. But wifey (not WiFi) uses a Dell. We're rarely (never?) playing Netflix/Tidal at the same time.
Getting repeater advice and advice to upgrade service ($250 to install fiber optic which would include a newer wireless router). Monthly fee would be the same that we're paying now but 20+ times faster. Next door neighbor owns the fiber optic service.
Either way looks like this free offer is going to cost me. 
Not sure what's your current internet speed but even a 5 Mbps connection would be good enough to stream tidal mqa without any dropouts provided no other streaming like Netflix is used along with tidal
The bottle neck for you is WiFi which due to long distances and other reasons makes the internet service slow for you
So I dont think you need to upgrade the internet seevice. If at one time cost of 250 USD you get 20 times faster internet for same monthly fees then why not

Makes it absolutely worth
But then you also need to solve the issue of weak WiFi to your music room