3x3 and 4x4 transformation matrices are not very friendly to start with. In LightWave's node editor I think they are even less friendly because there is no dedicated Matrix data type, so every operation involving matrices forces people to deal with the explicit matrix components which rises by a lot the price experimentation/iteration and makes the activity more prone to errors due to the amount of required connections and possible mis-connections.
One of the strengths of nodes is the ability to quickly change the tree algorithm, get instant feedback and produce better guesses to improve the algorithm. If a person has to deal with 7 connections instead of 1, that strength will be diluted or even rendered unpractical. After using XSI ICE matrix data type I can say LW matrix nodes force me to know more about matrix vector math than ICE nodes. That deterred me from experimenting, learning and tracing algorithms, faster if at all.
The easier it is to use something, the easier is to learn overlaying concepts, acquire a tool that gives desired results and not worry about the details.
The following image shows the same operation being done in the two systems and hopefully the contrast becomes clear:
Here's a mock.up of what the ports could look like in two essential places: "Item Info" node and Nodal Motion output. Please discuss which output would be better and why (Might be impractical to have both for evaluation consistency) and their interaction with IK.
Using ICE node as example, I gathered a family of operations that would be useful to have to deal with a Matrix data type. Let me know if something more would be useful and why.
Without wanting to get much into Quaternions and such (which I wouldn't mind having) here's what Fabric engine is using to pack transformations: http://docs.fabric-engine.com/Fabric.../Math/Xfo.html
I decided to make this a public Feature Request because given my background I could be catering solely to my personal needs and have some blind-spot that could impact other people. So feel free to jump in and discuss additions or changes to the idea or it's scope. After a while I'll do a proper feature request through the report system, if it seems fit.
PS: I had done similar thread before but it got "eaten" by 2016's database loss event.