You sound like a good candidate for a dynamo setup. A dynamo hub (
Shimano, SP or SON) if you don't mind rebuilding your wheel or
a modern rim dynamo (Velogical) if you prefer to completely disconnect when you're not using it.
Combine it with a higher end German dynamo headlight like a
Son Edelux II, the
B+M IQ-X, the
B+M Cyo Premium or
Supernova E3 Pro 2.
Most can be combined with a matching dynamo taillight or you can keep using your favorite battery powered rear light.