I think in the same way you do about 2 and 3 bullets…
About the first one; I haven’t tested but, connecting the latest node in your workflow (with a variable output port) to a ‘Timer Info’ node will provide you with a list of nodes in the workflow.
BR
With some string manipulation you can exclude the ones not containing ‘Deprecated’
Workflows are still folders with xml node files. So you could get “messy” and see whether this can be adjusted there (potentially with scripting then)
br