Since your husband only dives occasionally, and since he has gone 17 years without a dive light, I won't waste your time with $400 (or even $200) suggestions. Cannister lights and color corrected lights and all that are wonderful, but for joe-weekend couple-times-a-year diver, there are totally overkill.
The two most common types of lights around here are ones that 1) look kinda like a pistol and 2) smaller stick type lights.
PISTOL STYLE:
The pistol type are generally a little larger and generally a little brighter because they generally use bigger batteries. You can get ones that use either 4 C-cells or 8 C-cells. Cost and size goes up with the 8 cell models. They will normally be too large to fit in a pocket.
My buddy and I each have one that uses 4 C-cells and they work very well for each of us. I keep mine on a coiled lanyard that clips together and clips to my BC. That minimizes the amount the light hangs, and secures it to me, but still allows for good mobility when unsnapped.
The C8 or D8 models are much larger and a bit more expensive.
My buddy has the UK (Underwater Kinetics) C4 model, while I have the Princeton Tec version. In my opinion the UK model is much better because it has two bulbs, with a trigger that can light up either bulb. That means you always have a "spare" bulb in place, ready to use. My Princeton Tec has only one bulb, so I keep a spare bulb in my kit, but I need to be on the boat to change bulbs. Both lights have "locks" to prevent accidentally turning the light on.
NOTE: They also make rechargeable versions of these lights, but they are a lot more expensive. For the occasionaly user, it would probably not be worth it. Just remove the batteries whenever you put away your gear.
STICK STYLE:
There are a ton of options out there in "stick style" dive lights. I have a small Princeton Tec 40 (4 AA batteries) as my back up light, and I carry it in my BC pocket on a small lanyard. It has been nice to have that with me to "loan" to others on occasion.
Again you could buy small or large, with various sizes and numbers of batteries. Most come with a small attaching cord that you could put around your wrist. I always attach a lanyard that is long enough to reach anywhere (within reason) but keeps me from losing the light.
It mostly depends upon whether you think your husband wants a small light to go in his pocket or a bigger light that hangs on his BC. (I know the DIR and Cave guys will have all sorts of issues, but this is for a simple recreational diver that only dives occasionally)
MONTEREY:
I highly recommend carrying a dive light when diving in Monterey. Obviously you need a light at night, but I am talking about 100% improvement during daytime dives.
The first time I saw Monterey underwater with a good dive light, it transformed the underwater world. The world that was all just shades of gray below 40 feet suddenly exploded with colors. The Strawberry Anemonies and everything shone with such vibrance that it was absolutely a different world. I saw a huge dull gray sun starfish on a pipe out past the aquarium one day. When my other buddy shone his big dive light at the starfish, it was as if a red light inside the starfish suddenly turned on. The starfish virtually glowed red. I have never been out there underwater without a light since that day.
COMBOS - PACKAGES: Right now there are some really nice packages for sale at some dive shops. Both UK and Princeton Tec have combos that include a main light and one or more backup lights. Diver Dan in San Jose / Santa Clara has two combos for sale, one at 89.99 and the other at 99.99 that each include multiple lights. Many other shops have similar combos or packages. They can also set you up with a coiled lanyard.
If you have any questions, feel free to PM me.
Just my dos centavos, and only because you asked.
Wristshot
ScubaRon
