EDIT: I noticed that my original view which should be from slightly above and left is now not what I thought it was. View should be from {-0.25,0.25,2} pointed directly at {0,0,0}. For a while the "plane only" demo was viewing this correctly. Now this is viewing from above and right (not left, which it should).
Even with AxesOrigin I'm still running into some related issues. At this point I'm trying to get that AxesOrigin to be viewed from a particular angle regardless of the graphics present. I'll illustrate, where this draws the axis as I want it to be, and emphasizes the X/Y/Z via thick Red/Green/Blue lines on the axes. The other content is a plane with XY orientation. Then I'll add a cone to this by uncommenting the Cone in the code listed below, and you'll see the orientation change despite specifying both ViewPoint and ViewCenter. The first image is from leaving the Cone commented out, the second image is after uncommenting. The view changes when it should not.
The code, with Cone commented out which does what I expect:
Show[
Graphics3D[
{
RGBColor[1, 1, 0, 0.8],
InfinitePlane [ { {0, 0, 0}, {1, 0, 0}, {0, 1, 0} } ],
(*RGBColor[0.8,0.8,0.8,0.8],
Cone[ {{1,1,0},{0,0,0}},Sqrt[
2] ],*)
{Thickness[0.025], Red,
InfiniteLine[{0, 0, 0}, {1, 0, 0}]},
{Thickness[0.025], Green, InfiniteLine[{0, 0, 0}, {0, 1, 0}]},
{Thickness[0.025], Blue, InfiniteLine[{0, 0, 0}, {0, 0, 1}]},
{PointSize[Large], Black, Point[{0, 0, 0}]}
},
Axes -> True,
AxesLabel -> {
Style["x", Bold, Black],
Style["y", Bold, Black],
Style["z", Bold, Black]
},
AxesOrigin -> {0, 0, 0},
AxesEdge -> {{0, 0}, {0, 0}, {0, 0}},
Boxed -> False,
ViewProjection -> "Orthographic",
ViewCenter -> {0, 0, 0},
ViewPoint -> {-0.25, 0.25, 2},
ViewVertical -> {0, 1, 0}
]
]
What this produces when Cone is not shown:

After uncommenting the Cone, the view point changes and should not:

Notice that ViewCenter is told to look directly at {0,0,0}, and ViewPoint should always be from slightly above and left with positive Z going into the screen/paper. Instead, the ViewPoint is altered and forced away from explicitly set coordinates. My earlier failures seem to be partly related to this. Setting AxesOrigin was failing in some cases, and apparently this may be why (the view was changing in ways the AxesOrigin couldn't accomodate). For this case AxesOrigin is now closer to doing as expected, but the view changes.
View used to contain an approximate volume bounded by a bit more than one unit left/right/up/down/in/out from {0,0,0}, but adding the cone changed the viewing volume and shifted everything. Can I force view to about 1.1 units left/right/up/down/in/out from center so that my ViewPoint won't be forced somewhere other than where I specified? I think if I can force the viewed volume to stay constant, then I can add or remove components without everything shifting around.