As of this comment, supports: PHP, Python, RHTML, JavaScript, Smarty, Mason, Node.js, XBL, Tcl, HTML, HTML5, TemplateToolkit, XUL, Django, Perl, Ruby, Python3

I'm still certain about my original statement - A universal editor should not bundle more than syntax highlighting and some snippets. It's fine for IDE's that aren't designed to be extensible, and *only* support what it was designed to be thrown at, but even there it leaves a handicap, as the builtin versions usually have lots of holes (Visual Studio "Intellisense" or what it was called, can't find head or tail of the source tree at work for example, when I need to debug something on Windows)

Last note: I might pull down codeintel and see what should be wrong with it as well, but my time available for hobby-stuff is limited... So I can't guarantee progress in any near future

Any chance your tweaks are documented/posted/pastebinned anywhere? I love sublimeclang but it does seriously bog things down sometimes. I haven't really looked in to the choke points myself, though.

Auto-complete certainly isn't trivial, but it doesn't necessarily have to be inefficient either.

The problem with the current status quo is that there are multiple plugins (as you pointed out) with different behavior, using different mechanisms, and which aren't particularly easy to extend for new use cases.

What Sublime Text needs is a well designed API that will make adding proper completion possible. It _is_ possible to do this. You don't even necessarily need an IDE-level of integration. For example, Chocolat.app, a new text editor in the vein of Textmate/Sublime Text provides such an API here:

https://github.com/chocolat/completion

I would love to see a generic API in Sublime Text for this. That way, people can write their own completion engines. That is, a project indexer should go into ST2. The Indexer should call out to 3rd party indexing engines that are available to figure out how to parse all the files. SublimeCodeIntel is a nice idea, but it doesn't seem to work for me anymore (using it for PHP, Javascript, CSS, and HTML).

anyone used or heard of this plugin?

https://github.com/geniusisme/STsmartCompletion

This great plugin gives proper introspective autocomplete  for Python https://github.com/svaiter/SublimeJEDI

To help the developer implement this efficiently, it would be helpful for us to show some mockups of how we want this to look and exactly what/how the tooltip should contain inside of it in what contexts.

Also, the ability to have plugins provide the autocompletion text and do the parsing like SublimeJEDI posted above sounds excellent so that Sublime can do this correctly on a language-specific plugin parser basis.