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.. alternatively, you can increase the auto-complete delay - this gives the chance to type a few characters before the auto-complete list pops up.
I was unaware of this issue. The file setting "auto-complete":true causes auto-complete to be triggered automatically when typing. Changing this to false would then require Ctrl-Space (or Tab) to display/use the completions. This setting can be made syntax specific.
In the meantime, I'm quite proud of my own JS completions file https://github.com/agibsonsw/AndySublime

It's (fairly) complete and does useful things like pre-pending 'document', 'window' to certain methods/attributes.

But I've received limited feedback for it. I could revise it to automatically append a semi-colon to specific methods..