1) Try a save and reload. If you've been running around a long time, the map and objects you've seen appear to build up.
2) I believe it is intentional that you will exhaust the local resources and need to explore ever further afield to keep going. Try packing yourself a portable base, and drive out for a few days to get lots more resources.
4) They do seem to happen a lot when you least want them. If you drive far enough away that the map tile unloads, your base won't spring any more leaks while you're gone ;)
6) Wind generator is a classic suggestion, and a good one. The RTG is in fact quite overpowered however. It is particularly OP in comparison to real life units. For the same metal cost, plus the 6 radioactive ore, you get a full half of the power output of a solar panel, but the power flows during the night and never needs cleaning. Other than the starting equipment, my bases run on 100% nuclear power :)