A while ago I asked this question on StackOverflow:

http://stackoverflow.com/questions/7476220/image-source-completion-for-sublime-text-2

Code Completion that would access the filesystem would be very helpful, not alone for Images, but also for css/js files and so on...

Now I would like to ask this here. Is there anything planned towards this, are there existing plugins that are doing something like this? 

I would love to see support for multiple projects in a single window.

Personally I find the one-project-per-window approach difficult to use. Especially when I am working on two related projects, having access to multiple projects' files in one consolidated list would be very helpful.

Foo Project 1
    OPEN FILES
        (Foo Project 1's open files list)
    FOLDERS
        (Foo Project 1's folders)

Foo Project 2
    OPEN FILES
        (Foo Project 2's open files list)
    FOLDERS
        (Foo Project 2's folders)
etc.

Clicking on an open file or folder would switch the tabs shown in the current window to the corresponding project's open tabs.

With drag and drop support in the sidebar it would be easy to move open tabs and files between projects. 

This method could also help with ST2's problem of adding random unrelated/one-off files to the project that happens to be open/focused. By optionally having a 'Loose Files' project in the sidebar, opened files that are outside of any open project's folder scope could be automatically (or manually) put there without opening another ST2 window.

Allowing both multiple windows and multiple projects per window (and remembering these between sessions) could work well for certain styles of workflow as well. Some 'search in all this window's projects' function akin to (or replacing) Ctrl+P would also be dandy.

Tabs become pretty much unusable once there are too many open. You can't read the text, and the close box goes away. And if the close box is still there, I find myself clicking it by accident because the tab is too small.

I'm used to using Eclipse, and I like how they limit the number of tabs shown based on how much space is available. This way, you can always read the beginning of the file name, and the close box is always visible. When there are more tabs that can be show, a little menu shows up on the right. The menu shows the "shown" tabs in bold", and the ones that can't be shown are normal. You can then show a tab by selecting it from the list, and another visible one will take its place.