Looking for universal completion with simple UI

[dont.spam.earl@gmail.com]

Hi all,

I'm posting to ask about a completion model I have in mind. Before I code it up myself I'm trying to find any packages that already implement most or all of this functionality.

The Emacs Wiki Category page for Completion lists packages for minibuffer completion and text completion:
http://www.emacswiki.org/emacs/CategoryCompletion

I want a package for completion both INSIDE and OUTSIDE of the minibuffer with a universal UI:
- Minibuffer Input Completion:
  - finding files
  - switching buffers
  - apropos for functions and variables
  - and any other minibuffer history lists
- Text Completion in a Buffer:
  - code completion
  - executables/commands at a comint prompt
  - i-searching in the current buffer
  - cycling through killed text for yanking

Further, I want to navigate via a couple "dimensions" of context, both historical (previous inputs I've entered), and alphabetical (previous and next alphabetically, as in files in a directory).

The UI model and keybindings for this might be as simple as:
- show prefix candidates with TAB
- show substring candidates with S-TAB
- with candidates already shown, the second TAB/S-TAB would select the first candidate
- navigate candidates alphabetically with C-r, C-s
- navigate candidates historically with C-p, C-n

Do any packages implement this already?

Thanks,
Earl