I want to see SDL (with stereo visual support), a UI engine, high-level scripting engines like Lua, Python et al, an implementation of selective OpenGLES2 functions emulated using low-level PICA200 operations (a la Nintendo), possibly an altkernel/OS like Linux.
A standard plugin-based file manager/utility application would be nice. A plugin/applet can be made for all the assorted functions which were often loaded through multiple apps on the Wii. It should have the ability to figure out a file's unique type (like UNIX with "magic", not like DOS with file extensions) when you launch it, and pass the filename as an argument to an installed application such as an SNES emulator or media player.
On that note, certain homebrew applications should provide themselves to other homebrew as applets (like how the on-screen keyboard, NN sign-in or DLC eShop work).
You can use the file-browser applet within emulators to choose files.
You can use the video-player applet within a file browser to preview a video.
A metadata-editor applet provided by the file browser app could be used by a music player for editing a song's tags.
Homebrew devs should take full advantage of the OS and environment Nintendo gives to its own devs, rather than re-inventing the wheel countless times and throwing consistency out the window.
Given kernel access, I'd like to see a bootstrap like BootMii to enable full hardware takeover, and an alternative menu, loaded instead of the System Menu, which provides the option to auto-boot an executable from a set location, boot the System Menu, and hook the booted system menu to provide customization a la Priiloader. Patching out the region locks would be a cinch, at this point.
Also, along with hooking the system menu, the ability to (for instance) open a menu like Gateway does, from within the system menu, to enable/disable patches, cheats, etc. on other games.
A free-software or open-source implementation of NAND emulation would be nice, too.
As far as messing with installed files, an application which changes app metadata, and can modify settings in NAND, would be useful, for instance, to change a region on an installed title, or let it store more streetpass ID's, or change its system permissions.
Here's what I think is unnecessary, or just what I don't want on the 3DS:
- "Homebrew channel". Homebrew in general should be released in two main formats: an "NCCH" with all the dependent files self-contained for installing (as .cia) to NAND/emuNAND or SD, or (as .3DS/.cci) loading using a flashcart; and an executable object (like ELF, DOL, etc.) within a folder with its files.
- "USB Loader GX". Again, unnecessary as we have the ability to install .cia files, and flashcarts. Also, piracy is "evil".