I have an A-S201 in configuration as a short distance monitoring amplifier in use and am very satisfied so far. Of course, my Genelec don't need 140W per channel. But I can't imagine any application where permanent 2x140W is needed, even with a parallel connection of loudspeakers. Connecting speakers, regardless of their impedance, is always possible. However, it depends on the power profile of the speakers. However, according to the construction of the amplifier and the experience with other Yamaha amplifiers, it should be possible for a residential application without grilling the power amplifier. There is, after all, a volume potentiometer.
Many greetings and good luck with the experimentation