Nothing beats a good quality CAT5e or CAT6 network. Certainly not wireless and almost certainly not "homeplug" type devices.
I'm well aware that ethernet will pretty well always beat Homeplugs hands down, thanks (and that mains wiring was not designed for data transfer!), but if consistent performance twixt garage and office had been in the circa 120Mbps band (and sometimes as high as 180Mbps) that I am getting across two separate electrical rings between hall (HomeHub v1 primary WiFi access point) and upstairs bedroom (Homehub v1.5 secondary WiFi access point) I would have tried to live with it. (a) It's so easy, and (b) I already own a spare Homeplug. That the garage connection sometimes drops as low as 10Mbps Tx and Rx and usually hovers around 30 means it's a non starter!
As I sit here still awaiting the sound of a clattery diesel engine in white van outside I'm enjoying your game of tennis with M-B
30-all at the time of writing!