To allow users to specify a drilled hole, whether it is a mounting hole or part of a through-hole pattern, DipTrace provides edit boxes. That means that without keeping off-line notes, a user can end up with a collection of not-quite-the-same size holes, and then the user must trust the PCB manufacturer to decide that the same drill can be used for the 0.039", 0.03937", and 0.04" holes.

Instead of using an edit box to solicit a hole size, DipTrace should use a combo box, like the one used when DipTrace solicits a font size. Users could still specify oddball drill sizes, but they could instead (and more quickly) choose from a small set of standard sizes. For example, Eagle uses a range of standard sizes that starts at 0.5 mm and goes up by steps of 0.1 mm. Another range might be better, or it might be an option to load a range corresponding to the anticipated PCB manufacturer's favorite drills.

I will add your request to our feature list.
Notice, you can create pad templates and save them. It is more powerful feature than hole list. You can create as many pad templates as you want and choose one of them from combo box when you create a new pattern.