I think it is time to realise that AC generation was a bad idea and switch to easier to handle and store DC generation. We only have AC because we transmit power over a grid and this is more efficient. Base loads are required for this system to work but the system is not necssarily the best design now.
The majority of household power (heat, light) is used to heat the building - this is where some real power savings can be made mitigating further power production requirements. So with reduction in power requirements more can be derived from differing sources not necessarily from a grid.
"Nuke plants deal with decommissioning, solar, wind, hydro and tidal must cope with stupendously high equipment and territory costs, and geothermal doesn’t really exist yet."
Not one nuclear plant has made enough money in its active life to even vaguely pay for its decomissioning - as always this will be born by the customer / tax payer over and above what they have already paid in bills. Nuclear has had massive monetary input from government to keep the produced electricity price cheap and inline with other forms. Nuclear never has and never will be to too cheap to tax as was once mooted.
Geothermal does exist talk to the Icelanders - been using it for years. Geothermal suffers from being too inaccessable for commercial use away from vulcanic hotspots (usual in low occupational areas).
As for grid provide power what happens when you have a ice storm!! No grid at minus 30 and now feeling like an lump of ice. If only you had a super insulated house with simpe DC power requirements that could be met be a local CHP plant burning biomas.