Hey, thanks for the detailed feedback!
Regarding the hierarchy in the gui, indeed that is very simplistic still, but I think all the items you mention are already on the to-do list. You cannot yet duplicate a material (or any node), but that is also something that will be added.
Regarding the “add element” link in a mesh, that is something that will disappear in the next build; it’s only there because the gui is quite generic, so everything that supports such a function internally, is having it exposed in the current build (and in the case of a mesh step, or some other things, is not really applicable in a gui context).
Now, on the floating point error reports, I would really appreciate any repro scene, since these can be coming from anywhere, whether in our code, or in third-party code.
Regarding the invisible mesh, it could be that the parent transform has visibility set to hidden, but if not then I guess I’d need a scene to repro and see if there is potentially some bug. Regarding re-importing, that is another yet-to-be implemented gui feature, and it is also related to, for instance, importing/referencing external scenes, materials, etc.
Regarding the blend node connections, by default there is a filter active in the hypershade nodegraph:
If you clear that, then you should see what you’re looking for, but let me know if it ends up you are referring to something else.
On the last items, I think the problem is that the “glass” and “water” materials are a special type of material node, so the generic code dealing with material types is probably not filtering things properly — I’ll take a look.