Ok. Let's see this list. I'm interested in ways of improving SchemeSpheres, so this is quite useful. Keep in mind, however, that providing support for mobile devices brings complexity and limitations to what can be achieved.
 
- a collection of libraries that work well with Gambit

Well, that's certainly what I'm trying to do. However, there are some issues generally involving different syntax systems. I think there have been some improvements in this area recently in SS.
 
- some analog of ASDF that makes it easy to load all of these libraries, and easy for each library to declare its dependencies on others

That functionality is part of SS, even platform-conditional dependencies (like, GL or GLES for mobile for instance).
 
- an easily-accessible repository for the libraries

I'm using github. Installation is done through cloning a repo and running a script.
 
- an efficient way to collect updates to the libraries and make them accessible from the repo

Not sure what you mean by this. I'm using github, and people who have contributed to SS have done it through git forking and pull requests.
 
- a tool that enables you to quickly and easily search the libraries by name and description

That's a big TODO. I love this idea and I want to provide it. The first step is documenting everything, and that is a pretty big task.
 
- a tool that enables you to quickly and easily download and install any given library

The tool is called SSpheres, and does this. Is not perfect, as many things being improved, but it works.
 
- an easy way to tell the tools about nonstandard and local repositories

This is important, and easy to add (although not available at the moment). I thought about it as a necessary functionality since the beginning.
 
- an easy way to tell the tools that you want a specific version of a library, or multiple versions of a library

Same here. I intend to implement versions with Git tags for this. At the moment "versioning" is just used for differentiating targets (such as "debug", "optimized", etc..)

 

Thank you for your interaction, I really appreciate.