Yes, lighter is definitely the trend these days and the heavier shafts (70g+) tend to have a very stiff tip and low-launch/low-spin profile. And not sure what flex you need, but many of the heavier shafts are only available in the stiffer flexes.
That being said, one that comes to mind off the top of my head is the Graphite Design G-Tech which can be had for around $20-25 and it is 74g mid-launch/mid-spin.
In regards to swingweight, keep in mind that it takes 9g of shaft weight to change the SW by 1 point. So a 66g shaft would only be 1SW point lower than a 75g shaft, and 1SW point can easily be made up by adding a mere 2g to the head. The end result would be a club that has the same SW as one with a 75g shaft, but the total club weight would be about 7g less. Just some food for thought....
