Papa Tom, you've reached the point of analysis paralysis.

Flip a coin. Heads you go get a very nice dyno system. Schmidt SON hub, Edelux light, you're right at your budget, you won't have to worry about it again. (Until you want a new Luxos IQ2 U, but you can't get one of those anyhow.)

Tails, take $200 down to the nearest good bike shop or REI. Pick the nicest light that you can find for under $150. You want the $175 system? That's why you brought $200. Ride it all winter, enjoy. You can repeat next year, if there's anything better that you want to spend your money on.