I should have dug more before I asked this... They are called "Key Bindings" and every single one of them is configurable from within a text file. Click "Preferences" > "Default Key Bindings" to view them. Copy and paste the ones you want to edit into "Preferences" > "User Key Bindings" to and change to your hearts content.
Here is the documentation.
My problem was that I was searching for "keyboard shortcuts" instead of "Key Bindings". Whoops...
To specifically address the question I had, about how to replicate the Delete, Home, End and Arrow keys, I have modified my "User Key Bindings" file to look like the following:
[
{ "keys": ["shift+backspace"], "command": "right_delete" },
{ "keys": ["ctrl+backspace"], "command": "right_delete" },
{ "keys": ["ctrl+j"], "command": "move", "args": {"by": "characters", "forward": false} },
{ "keys": ["ctrl+l"], "command": "move", "args": {"by": "characters", "forward": true} },
{ "keys": ["ctrl+i"], "command": "move", "args": {"by": "lines", "forward": false} },
{ "keys": ["ctrl+k"], "command": "move", "args": {"by": "lines", "forward": true} },
{ "keys": ["ctrl+shift+j"], "command": "move", "args": {"by": "characters", "forward": false, "extend": true} },
{ "keys": ["ctrl+shift+l"], "command": "move", "args": {"by": "characters", "forward": true, "extend": true} },
{ "keys": ["ctrl+shift+i"], "command": "move", "args": {"by": "lines", "forward": false, "extend": true} },
{ "keys": ["ctrl+shift+k"], "command": "move", "args": {"by": "lines", "forward": true, "extend": true} },
{ "keys": ["ctrl+alt+j"], "command": "move", "args": {"by": "words", "forward": false} },
{ "keys": ["ctrl+alt+l"], "command": "move", "args": {"by": "word_ends", "forward": true} },
{ "keys": ["ctrl+shift+alt+j"], "command": "move", "args": {"by": "words", "forward": false, "extend": true} },
{ "keys": ["ctrl+shift+alt+l"], "command": "move", "args": {"by": "word_ends", "forward": true, "extend": true} },
{ "keys": ["ctrl+,"], "command": "move_to", "args": {"to": "bol", "extend": false} },
{ "keys": ["ctrl+."], "command": "move_to", "args": {"to": "eol", "extend": false} },
{ "keys": ["ctrl+shift+,"], "command": "move_to", "args": {"to": "bol", "extend": true} },
{ "keys": ["ctrl+shift+."], "command": "move_to", "args": {"to": "eol", "extend": true} }
]