None of the shown semi-automatic hatching methods is perfect. The density of the hatch presents the amount of shading caused by geometry and light conditions. The directions of the lines hint the directions of the surfaces.
The lines are not always straight, They can be drawn to present also the directions of non-planar surfaces - an extra portion of information to reduce the needed density of lines. The "presenting also the surface direction" -idea is used hundreds of years because the reduction of the amount of needed lines speeded up substantially the making of wood carvings and copper engravings for image printing. Of course, it was as useful in drawings on paper, but there one has also other shading possibilities.
The clean uniform straight line hatch is too clinical, it makes all look machined and planar. The blue curved hatch implies an impression of curved surface. I guess you didn't plan just this surface should look curved. The effect is difficult to control, it does what it does, no matter there's many numbers to be set. In theory the effect has an adjustable amount of randomness which in a lucky case could simulate manual scribbling.
The green version of your examples offers the best possibilities to present also the directions of non-planar surfaces. You can limit it to a certain area by using a clipping path. Making one is now easy because the shape builder is recently added to the repertoire.
The next image (drawn for this answer) has hatches which are made by interpolation. The excessive ends are clipped with clipping paths.
It looks like it has also curved areas, but it doesn't at all have the elegance of manual crafting. I'm sure the best result can be got by drawing the lines manually one by one. Interpolate is still mechanical. In addition using plenty of effects somehow makes Inkscape to hang itself soon. The program becomes at first slow and finally stops to respond. Drawing lines manually keeps the number of nodes and possible accumulated crap in the computer memory in control and the program stays responsive longer.
You may say that drawing so many lines one by one is error prone and needs much work. Sure, but when compared to metal engravers and people who draw on paper you at least have UNDO which affects only a single dot or line segment.