Only if you already use resistive heating. Where I live I have a need for heating, but no cheap electricity, so my heating is natural gas and a heat pump. A miner would be a net loss for me.

I'd say so. I might look into getting a bitaxe this year for solo mining, In my opinion all plebs should look into solo lottery mining just as they should probably run a node and self custody as well.

Jam and Robosats are both apps on Start9, you can try to earn coinjoin and non kyc arb yield on your corn. Probably would earn more with an S9, but the "yield" comes from assisting other plebs with privacy and anonymity. Running a lightning routing node is difficult and will most likely result in you losing sats, but i'm bullish on (in the future) providing lightning liquidity for extra sats.