what are the top level subsets/domains of ML?
Google (in images!) on 'machine learning cheat sheet', to find an example like this:
https://docs.microsoft.com/en-us/azure/machine-learning/studio/algorithm-cheat-sheet

So you are well on your way in identifying all kinds of techniques, but you may want to turn your plot 'sideways', e.g. two-way / multi-class classification are problem (sub)domains and result in different recommended machine learning techniques.