No plans to break it up into pieces (apart from already consisting of modules). It does one thing, it just happens to be a big thing :-)
If you have a mac of Linux box you can have it up and running in 10 minutes. Multi-node production deployments are no different because Vespa manages the nodes, not you directly.
This may be a difference in mindset, but we generally let apps define the schema, so it's in the developer's realm of responsibility, not an operational concern. We also have apps (currently using Elasticsearch) that manage the schema automatically, derived from a high-level application definition. With ES, the app creates a new index with new mappings, shovels data into the new index, and then activates the new index. But it uses the ES APIs to do this, and restarting anything is not on the table.