Lighter wheels can be good. I have decided (at my weight of 130 pounds) that the lightest wheels don't make any sense for me. Sure, if all I do is climb hills, any gram I can save is worth something. In general riding, the lightest wheels I've owned were worse than the ones I'm riding now. The lightest wheels I've owned were about 1380 grams. The ones I like best now are around 1550 grams. The difference is the ability to hold speed on a ride that is on rolling terrain (what I ride most).

You can get the wheels I like best for about $625. If you are careful, you might be able to get comparable wheels for less. Don't overspend and don't expect more from wheels than you are likely to get. Just my experience.