Code completion keyboard shortcut clashes with default system-wide shortcut on Mac OS X

I believe Command+Space is the default OS X key binding for spotlight search

Cmd+Space switches the keyboard layout, while Ctrl+Space opens Spotlight. (I just tried to reset my keyboard shortcuts to defaults, and this is still how they are assigned.) Perhaps Cmd+Space is the default for Spotlight if the user only has one keyboard layout set up, but I think this would be strange as it would mean the shortcuts would suddenly change when the user added another keyboard layout. On another note, all single-modifier shortcuts will the space bar are already taken (Cmd switches the keyboard layout, Option inputs a non-breakable space, Ctrl opens Spotlight, Shift… well, that does not quite give a shortcut, as people will expect it to just enter a space), as are Cmd+Option+Space, Option+Ctrl+Space and Ctrl+Shift+Space; it is hard to find a good shortcut for code completion at all.

By the way, in Xcode, the default shortcuts for code completion are Option+Escape to display a list of possible completions and Ctrl+. to instead complete the current word using the first possibility or cycle through them if pressed repeatedly.

Hmmm... I also would like to use the escape key for completion. So I came up with this key binding:

{ "keys": ["escape"], "command": "auto_complete", "context":
[
{ "key": "selection_empty", "operator": "equal", "operand": true, "match_all": true },
{ "key": "preceding_text", "operator": "regex_contains", "operand": "[\"a-zA-Z0-9_]$", "match_all": true },
{ "key": "following_text", "operator": "regex_contains", "operand": "^(?:\t| |\"|'|.|,|\\)|]|$)", "match_all": true }
]
},