The most frustrating part of building in this game for me is the piping and wiring. Is there any chance at all that you might be interested in doing a corrected set of those?

To correct them fully would need a mesh person but as I understand it you are already looking for one. Ideas like half length horizontal/inclined/vertical elements, hitting "e" to rotate the direction when snapping a horizontal to a vertical (45 degree increments would be awesome), a vertical cross, horizontal and vertical tee (3-way) with option to flip directions, horizontal and vertical bends (2-way) with rotate option, etc.

The fella that did the bridge mod put in a way to change the size of the bridge. Maybe it would even be possible to use this feature to have adjustable length pipes?

These types of improvements done with your height check, collision check and pick up ability would be absolutely phenomenal in my opinion.