I'm paying around 0.12€/kWh on a prepaid yearly contract. I've got a bunch of RX 5500s and RX 5600s running KAWPOW !!!
My contract locks me in at 18kW permanently but I'm only pulling about 15kW right now, so those extra 3kW are going to waste if I don't put them to work.
There's no breaker at 18kW, it's not hard limited, but anything above that gets billed at a much higher rate.
You're right that pumps aren't what they used to be, but with the electricity already paid for regardless, it costs me nothing extra to keep mining.
Worst case I'm heating my office for free in the winter time

In Russia, we install 15-kilowatt breaker in private homes, but electricians can install a breaker that, according to the documentation and appearance, appears to be rated for 15 kilowatts, but in reality, it operates at up to 30 kilowatts.

If I were you, I would probably mine BTC and BCH solo.