I find it hard to sell working in Houdini to less experienced colleagues, they don't really buy the "give it some years, and the UI will grow on you" vibe.
Some good things in your list, but I gotta take a tiny exception to the notion it takes "years" for the houdini UI to not be a stumbling block to using the application. That is nonsense. Unless you've never used a piece of 3D software, it doesn't take more than a week or two to come to grips with it.
That sounds more like those co-workers simply don't want to use it. I mean, 3DE and XSI, and a bunch of other tools have/had horrendous UX, heck some internal tools at big VFX companies whose UI looked like an amiga in the 80s.
But none of them actually couldn't perform their job, a lot of the time making the highest end VFX out there, due to the UI.
Could/should things be better? Of course. Does the UI/UX actually make it hard/impossible to do your work? Not a chance, and
if it is, then maybe it's the concept of houdini they are struggling with, not the actual UI.
As Henry mentioned, go drop, merge, swap inputs, yadda yadda, in any other DCC that has nodes, they are pretty much 80s schematic trash in comparison.