Kanazawa is great, and I'd suggest it over Niigata any day.

It has one of the most famous gardens in Japan, and although there won't be much blooming at that time of year, you can see how it's laid out.

It somehow escaped being bombed during the war, so it has a lot more old stuff than the average Japanese city.

Touring the so-called "Ninja temple," built by a paranoid and full of boobytraps and false doors and windows is a fun tour.

The central marketplace (covered) is great for walking around.

If you're into traditional crafts, Kanazawa has 'em.