For the scope of defining parametric constructs like stairs, windows, doors, pergolas, railings, etc. which is the best tool among Geometry Nodes vs Sverchok vs Sorcar?
I know it’s a general question but it has to be since it’s a new approach for me to try to customize some work without previous knowledge of any of the above, it’s a question where to start.
I know of and don’t search for existing addons that do the job like Archipack or others.
Personally, I think it’s a geometry node. 
One thing to note is that Sverchok and Sorcar (and Animation Nodes for animation) started before there was anything like ‘procedural geometry generation’ for Blender.
Each one of Sverchok/Sorcar was developed by their own teams independently, however once Geometry Nodes got into production it looks like the score between these three got settled. Now Geometry Nodes is the official solution and provides standard knowledge and compatibility among a wide range of collaborators and available assets on the market.
While the other two are third party and perhaps have some unique nodes (eg: sverchok has neural nodes!). It really depends on whether or not you have very deep knowledge between the three and you know exactly what you want to use, this suggests that only node-experts can figure out the differences and cherry pick each best features when needed.
Makes sense. Words of an expert?
No, I do only the basic stuff. Usually I look on twitter #geometrynodes and see impossible node setups. 
I didn’t tried Sverchok and Sorcar, probably both are a little bit more advanced since they are older, but I’ll bet on geometry nodes anyway.
What you’ll probably miss in GN is a bevel and a few modeling functions. But it’s always possible to work around those limitations in most cases.
The objects you talk about doesn’t seems to be the most complex either.
The good thing about GN is that it’s there by default, sending your file to someone else isn’t a problem, and it’s going to evolve and stay maintained.
If you plan to reuse your procedural setups for the years to come that’s what I’ll bet on.
Needless to say that you’ll find a lot of resources ( tutorial, assets ) based on GN.
If your project is a one shot, and you don’t plan to keep these assets after that, maybe it’s worth testing the 3 systems to see which one you prefer and which one is more adapted to your project !
Sverchok has bunch of advanced stuff and extras compared to GN. The main advantage of GN over Sverchok is the speed, and it works as a modifier. The main advantage of Sverchok over GN is that it has many nodes and algorithms implemented already.
Look how complicated it is to make a loop cut on a cube mesh! with Geometry Nodes:
I’m trying to start learning but querying the geometry should be far easier and more intuitive.
This seems so weird that I assume the programmers focus has been targeted to other uses of geometry nodes. I have seen amazing things done with them.
yeah you pick something difficult.
But in your example it might be much simpler to generate the cube with enough subdivision.
I suggest you first look at the tools and from there see how you can use them to get to the result you want. Rather than look for the most obvious functionality to get to a result.
A lot of common tools are missing or made by other with nodegroups.
This topic got a lot of interesting resources : Let's regroup Geometry Nodes Groups - Resources and Links
Personally it took me like a mount to do just tests to learn the basic tools. For instances curves tend to be more versatile than mesh operations. I tend to use them much more than in regular modeling.
Have fun !
I wanted to use sverchok and sorcar (and animated nodes) since i discovered it but almost never had time for it ( 
excuses excuses…) and i do not clearly remember which one was object based and which geometry based ( or something like this… has to do with the workflow / mindset)…
But maybe this little discussionis usefull:
especially the last one:
Also we might need “send from SVerchok into Sorcar” maybe
Done!
And (of course) this BA threads of the original authors (AFAIK):
So as i (not very clearly) said above: it’s about the workflow… and different approaches…
Someone could do this also completly in python and using the blender-api… and sometimes a code-node would be helpfull… oh wait i think one of them has such thing…
yes, sverchok has several nodes to deal with python code:
exec node - directly python coding from node interface
ScriptNodeLight - code from text file with simple inputs/outputs definitions and amount of examples
formula node - one-line codeing tool from nodes interface
enjoy
