1 and 4,
About the 1), I only solo mine BTC and BCH. BCH solo mining makes me living (always swap my BCH to BTC lol), and solo BTC is like a lotterie for me.
I had to stop mining Scrypt when most of my L3 hashboards died one by one. I won't complain, they were over profitable but for now I don't want to buy L7. Phil, do you convert your mined LTC + DOGE to BTC or do you hodl doge? LTC looks more and more like a safe bet IMO for the next bull, even if I don't hold any, I think it could give great profits.
As long as I have my current contracts (electricity), I will continue to support the XMR network. I have a pretty massive hashrate thanks to engineering CPU samples. It would be a loss to mine with a 0,1 or 0,08 usd per kwh, but for now I am far from these ranges so I continue. I will have to stop soon as the price will for sure go up, we will see..