Not a vibration table but you can hold a massage vibrator (gently) against the side of the mold. Too much vibration can add bubbles.
You can get a finer finish by changing what mix recipe you use. What recipe are you using?

I found that air bubbles migrated towards the vibrator - if held at the bottom of a mold/top of the piece, that's where the holes appeared.

On the other hand, a contrasting pigmented cement filler can add interest, especially if you polish (but don't polish - big pain in the rear).