Climate policy?

I am not a climate scientist but have been reading about the issue for fifty-years and have my doubts about several aspects. I do believe glaciers are melting, the Arctic is warming and we should reduce our dependence on fossil fuels. Our reserves of fossil fuels are finite and I would like to leave some for our descendants.
The fact that carbon dioxide is a greenhouse gas and more will increase the Earth's temperature is a fairly simple one. Another fact is that greenhouse gasses work like insulation. If a certain concentration retains 50% of solar heat, doubling the concentration will retain 75%. Doubling again will get us to 87% (where we are now) and doubling again will get us to 94%.  This is an example of diminishing returns and we are already close to the maximum theoretical capacity for carbon dioxide to achieve. To get a catastrophic event we have to bring in the release of methane from marine clathrates or a similar effect multiplier. This did not happen in the Medieval Warm period or other eras warmer than present. 
Medieval Warm Period - Wikipedia Besides French taxes on British wine, we keep finding more Viking farms in Greenland as glaciers melt. Obviously, the glacier wasn't there when the Vikings farmed there. There is further evidence including 800-year-old penguin fossils revealed by glacier retreat in west Antarctica. New Archaeological Finds Shows Earth Is Typically Warmer than Today - ClimateRealism  So we have eras warmer than present without carbon dioxide which hints other factors caused that warming. Perhaps the present warming is a return to previous warm climate. The next thought is that shutting down our fossil fuel economy (that feeds and warms 7-billion people) might NOT end climate warming.
So here we should look at root causes and worst cases. One root cause of fossil fuel use is our large population. Industrial nations have a birth rate lower than replacement. Industrializing the third world may eliminate the pressure of ever-growing population.
The Milankovitch cycles of the Earth's orbit suggest lowering temperatures for the next several thousand years. This will result in a glacial advance with up to two-miles thick ice over New York City. This just might reduce our agricultural capacity to feed the world. Maybe. 
On the warmer worst case, the previous citation mentions Svalbard being 7 degrees Centigrade warmer just 10,000 years before present. It didn't kill off the polar bears and humans thrived. Yes, it would require work and money to adapt, but far easier than all of us looking for caves in a glacial age. Your opinion may differ.
One recent policy triumph is getting the Chinese to stop building (dirty) coal plants outside of China. Of course, the current alternative is burning coal, wood or camel dung in the home for cooking and heating. This exposes millions of women to black lung disease and releases megatons of soot that contributes to glacial melting. Watch Ice Station Zebra with Rock Hudson. Power plants easily precipitate that solid carbon.
Another triumph is the decision to shut down the carbon free nuclear plants over the next five years.  These plants produce 20% of the total electric power in the United States and a far higher percentage of our carbon free electric production. The replacement cost will be three times as high for the solar and wind plants due to the intermittency of such power production PLUS another big expense for batteries to store power for summer nights and long winters.
California is increasing demand for electric power by encouraging electric vehicles and electric heating for homes. California is banning natural gas lines in new homes for cooking and heating. California is also offering incentives to replace oil or gas heating with electric heat pumps. Some decades past, the power output curve of rooftop solar panels was praised for closely matching the electric demand of air conditioning. The cooling demand in California is 1000 degree-days, while the heating demand is 3000 degree-days, in the winter with less sunlight. The typical household demand for electricity, today, is 25 kilowatt-hours. The battery for a Tesla is 80 kilowatt-hours.  This is going to take a lot of solar panels. At the same time, California is ending incentives for homeowners to install rooftop panels. California is about to stumble in the climate fight (msn.com) If we do not generate the power on our rooftop, we will have to import it over the grid.
I see we are increasing our demand for electricity and do not see we are increasing production in proportion. If this is the situation, we will see more backouts. We have one in the Sierra Nevada mountains with customers without power for a week. I hope they have wood stoves. Rick