I have a Gazelle Toer Populair from about 2010, which has hub powered
lights. And I like that. I don't have to remember to swap the
batteries once a week. I don't even have to remember to turn it on,
because it has a photoresistor in it somewhere.

BUT! The front light is a bulb, not LEDs. Not a big deal, I can just
buy a new bulb. Except that on the bulbs that jaycar and bunnings
stock, the glass bit is sliiiightly too wide to fit in the housing.
(The jaycar bulb says it's "pre-focus" and I want more like
"lens-ended".)

In theory I just go to Bike Life (my LBS) and say "me bike no work. u
mak fix pls" and they deal with it, and I don't have to care. But in
this case it seems even Gazelle's australian mob don't know how to get
the flipping bulb.

All this has reminded me that I'd really prefer if the headlight was an
LED array anyway, so I'm wondering has any opinions on whether that's 1)
possible; and 2) sensible; and if so, 3) how to do it.

AFAICT I can't just get LEDs in the bayonet bulb form factor, and just
plug it in, and be done. I can handle a soldering iron if I must, but I
don't really want to have a lunchbox of loose bits duct-taped to the
handlebars.

I suspect the responses are all gonna be "I hate dynamos! Batteries are
not that hard, just HTFU" so I haven't bothered to dig up hub specs &c,
but I'll do so if there's interest. The bulb claims to be a Philips
HPR60, 3.6V 2.4W.