PS Audio was sort of ahead of the curve. There were some smooth and musical solid state amps in the '80s, and PS Audio stood out as one such. I have an Amber Series 70 power amp and it's another example. I think hanging tight with what you have is a good idea.
Since the Arros are bi-wirable/bi-ampable, if you find you need more power, find another '80s-era PS Audio amp. They should be pretty inexpensive by now. Then, for the price of one used amp you could bi-amp and double your power to each speaker.
In fact, here's a same-era 70 wpc PS Audio amp with a BIN of $200.
Since the Arros are bi-wirable/bi-ampable, if you find you need more power, find another '80s-era PS Audio amp. They should be pretty inexpensive by now. Then, for the price of one used amp you could bi-amp and double your power to each speaker.
In fact, here's a same-era 70 wpc PS Audio amp with a BIN of $200.