Any jig with wheels that run on the stone, such as the Eclipse that I use, will have a limit to how short a blade can be sharpened to the desired angle, caused by the laws of geometry. The Eclipse has the correct protrusion lengths for 30° and 25° cast into its body, and if you cannot achieve that much, you cannot get those angles.
With wheels that run to each side of the stone (and it doesn't have to be the bench surface) you should be able to accommodate any length of stone by adjusting the height of the blade. It doesn't have to be a high-tech item, there are plenty of do-it-yourself designs available
Les