Folded Protein Chunk Dimensional Classification?
CATH
The CATH database classifies protein by fold: https://www.cathdb.info/
So the value from that is probably the most useful for you.
Crystallographic conditions

pH
Salinity
Dissolved Sugars
Reducing Agent Concentration

Your crystallising conditions do not mean much. They are a solution that is close to precipitating your protein but slowly enough for it to crystallise. A protein can crystallise under multiple different conditions and a crystal may be chosen simply because it is a lower index well in the Hampton screening conditions...
These mean very very little. And unless you are planning on doing ML to determine the best screening condition these should be avoided.
Data from the PDB
You have probably noticed that the only stats PDB/PDBe give are crystallographic, like space group, unit cell dimensions, resolution, completeness in shells, Rfree, Rmerge etc. So nothing there is of much use... except for bound ligand. Often this is the cofactor, but often it's a cofactor analog or a product (as opposed to the substrate). But that information can come from Uniprot etc.
pH
A solution has a pH, a protein has a pI. At a pH equal to the pI it will be neutral —and less insoluble. ProtParam can calculate the pI from a linear sequence. However, surface charge totally shows different spots. APBS can map the solution to the Poisson-Boltzmann equation to your protein. There is a PyMOL wrapper, a Pyrosetta wrapper and more. But you still would need to some stats and 3D operations to convert it into a small vector of values —rototranslations and projects are not for the faint of heart or in a rush.
Melting temperature
BRENDA has lots of enzymatic data on enzymes including melting temperature or kinetics at different temperatures (which follow the Eyring equation (TST), until MMRT kicks in) which could be useful.
For a given protein you can calculate the relative folding ∆∆G (eg. with Rosetta Score), which is a proxy to melting temperature in a buffer it is happy in.
Despite paining me to say... some fanciful Poisson-Boltzmann map derived vector and ∆∆G are probably all you could get from analysing structures. Whereas the rest are from CATH classification and other databases that are not structure based.