The easiest way to switch to dynamo power is by getting a complete off-the-shelf front wheel. This one is based around Shimano's six-volt, three-watt hub (DH-3N72) laced up with 36 DT Competition spokes onto the excellent DT TK7.1 rim.
After a good few long rides, the rim stayed straight and true, and the hub performed well; with nothing pulling load from it it feels like a normal wheel, with no noticeable drag.
More impressively, even with lights and a phone charger running, the hub still didn’t feel as though there was much drag. If you’re looking to switch to dynamo power, then this very capable all-rounder would make a great choice.