To make the plastic socket above more robust... could also solder some #14 wire to that exposed tab (keep the bulb in to help dissipate heat from the soldering iron) ... heat sleeve the connection and glue with black Silastic (or pot the end entirely) and crimp an inline spade on the other end of the wire, with cable ties either side if it's loomed.

I too have has some issues with the sockets and was looking at options the next time they act up... good thread!