Hi Pior - mostly I've assumed that if you're doing something that requires 3D sculpting like point manipulation, that you would be doing that type of model in a polygon modeler that focuses very much on that kind of model construction.

But for the particular kind of "move upward in z" motion that you're talking about in your screenshot graphic, you can get that particular case without leaving the 3D view if you have "Straight snap" turned on in the bottom toolbar, here:



When enabled that enables snap lines to help both draw lines to be aligned to the x, y, or z axes and also allows you to do movement along the z axis while in the 3D perspective view, you just move your mouse along the z direction with Straight Snap enabled, and if you are close to the z line a snap will engage that will show an axis line with a "z" label on it and while you move along that line you will be moving in z, like this:




I think before you edited your message you wrote something like "even with all snaps turned off" you couldn't get the result you were looking for - but that's the issue, you need to have straight snap turned _on_ in order to get a z axis direction snap going, if you have all snaps turned off you will only be tracking along the base plane and not have any other kind of motion, you have to have straight snap turned on in order for that kind of x, y, and (in the 3D view) z axis snapping to be engaged.

Hope this helps!

- Michael