The place to pose that question and raise an issue is here:
[http://mayafeedback.autodesk.com/forums/160518-small-annoying-things-to-fix-in-maya-forum](http://mayafeedback.autodesk.com/forums/160518-small-annoying-things-to-fix-in-maya-forum)
It is a similar limitation with sliders and this kind of function not only in Maya but in all software. Even if you changed it to be the same as other sliders in Maya that would be setting it to a new range by entering a value beyond the default range. However you'd think you would at least be able to do that as you can with sliders. But I don't know if it is possible to have it unlimited.
Another issue you may or may not be aware of is that these values can be animated. That may well be related to setting limits. I Don’t know.
However, in this case, with modeling in particular, the issue is that the Maya default unit is very small. To model objects to scale in Maya for example - which you should be doing for many reasons - a 1meter box is 100 units.
A character in Maya to the scale of the default HIK rig for example, and that also fits the default scale in MotionBuilder, is a little under 200 units tall.
But compared to that, the default grid and object sizes are extremely small. 1 Unit for a box.
So you can scale it up to 1 meter interactively. Too small for cars or larger objects.
The default nDynamics scale is that 1 Unit is 1 Meter so if you are modeling to scale at 1unit is 1 cm then you have to adjust the space scale of the Nulceus solver to .01
I am not sure what the solution is here for this given the more broader issue of the Maya defaults. At the moment it does seem like it is entirely in the hands of the user which is why I suggested scaling first which is the way I work.
But make some suggestions over at that site and see what responses you get.