I think your analysis is good and a reasonable way to break the issues into a manageable discussion. As you know, there is a huge amount of repetitive circling and meandering in the discussions here. It's difficult to make a a logical point in one area (a specific topic within one of your categories) without someone kind of missing it, for blowing past it by bringing up an annoyance related to something else. That's not to say that I think the forum will actually embrace your, or any particular framework for the discussion to get more productive
Here I take somewhat of a departure. I think a lot about the hardware suite and what it can do in concert with the developing software, and how humans deal with an arguably inadequate bio-hardware suite.
I do think the NN can learn to do great things with even mediocre camera images, yet I've been an advocate for more and or better camera angles. Sometimes people push back on such suggestions, and talk about how there is a 360° view, or that humans can drive just fine with only two eyes, even one.
Aside from a lot of specific discussion about perspective, geometry, occlusions in the environment, resolution and all that, I take the general position that there are some relatively inexpensive "superhuman" capabilities that can be leveraged to make up for obvious deficiencies in the current state of the self-driving perception and planning software.
For example, the simple fact that the car does have full-time surround vision (even if imperfect) is a superhuman capability that we wouldn't trade away for a swiveling, bobbing, only centrally-sharp pair of cameras behind the windshield. That would be silly, more expensive and less effective. So let's embrace what a bunch of inexpensive cameras can do and maximize that.
If I had been there in 2015 or so, I think that I would have argued for a little more and or better placement, for an exterior microphone, perhaps a set of IR illumination LEDs - all of which were available and inexpensive at the time, it would confer certain "superhuman" capabilities that I think would have greatly simplified some of the problems challenging the project right now. Man-years of development in managing creeping behavior, vulnerable or hostile actor persistence and prediction, parking lot challenges. We can say that the software can eventually overcome, but I think Tesla would be farther ahead with some of that 2015 available hardware, had it been included.
What about lidar, HD radar, Imaging sonar or other exotic sensors? People gloss over the key fact that those were unavailable at a practical cost and performance level when the 3 and Y were being planned. That is beginning to change and we might see HD radar for example.
But my point is that even with the 2015-ish level of hardware, Tesla could have leveraged it somewhat better and we'd already have a smoother and more confident FSD experience.
And this is where we come back to the thread topic: perhaps the cost of an HW4 retrofit, full or partial, would pay dividends as the development team could move ahead knowing that the whole feet could leverage off of this and they could reprioritize on next
