This x1000

As far as $ per gram go, tires are the most effective way to reduce weight. On one of my builds it cost about $200 for a wheel that dropped me 200 grams and $29 for a tire that shaved off almost 300 grams. With a decent amount of caution I've been flat free with much thinner tires - depending on how your roads are, some thick urban-armor type tire can be overkill and overweight.

Specifics if anyone cares: Wheelset went from Eighthinch Amelia to a Alex DA28 & All City track hub. Tires went from Thick slick urban elite to serfas seca RS