Make more things searchable

I'd like to be able to search for related items, or groups (without hand-coded search) and my-random-object in my extensions.

Would be great if there was a simplified way for making things, from both in core and as part of my extension, easily searchable by Solr. I'd want to not have too much setup, and would want to be able to search for a specific thing (group, my-random-object) or across all things (find 'gold' in anywhere it is mentioned). Cores can be created programmatically although I think it still requires symlinking a schema file.

Obviously this would require an extension to define a schema.