I am having the same problem with Dasher. It's not "awful" but enough that I notice, then I don't want to use the image. His body is supposed to be solid and I want it to be smooth and solid!
First, make sure the ink pad you are using has enough ink. If it's a pad you've had for awhile it may need re-inked.
Here's what I did to finally get an image I consider acceptable.
Using a brand new Cherry Cobbler ink pad; I first ink up the Dasher stamp with Versamark, then ink it up with the Cherry Cobbler. One after the other, not stamping in between. So you have two layers of ink on your stamp.
I put my piece of paper on top of a larger post it note pad. Stand up, then stamp down on the paper, laying my hand flat on the wood I lean down into it; count to about 10...then carefully lift up. This seems to get me a good solid image most of the time. It's not mistake proof but it's stopped me from throwing out a lot of stamped images.
Either zap the image quick with a heat gun or set aside to let dry a little bit since with the Versamark on there it will stay "wet" a little longer and could smudge if you try to handle it too soon.