If the glass is simply a flat sheet, you can fire it to about
1350-1400 in a kiln (the temperature to use depends on the size of
the glass, the kiln and how smooth you want it) to "fire polish" it.
This will soften the appearance of the sandblasting.
Alternatively, there are companies that do acid polishing.
A good board to post this question on, if you don't get a response
here, is the warmglass board for kiln-worked glass artists. It's at