Agree. We try to solve the problems progressively. The connected model support is a foundation to those features. See http://strongloop.com/strongblog/defining-and-mapping-data-r.... Basically, we build models that relate to each other, partition the data graph with links, and expose them as REST APIs that can be used to navigate and aggregate the information from various data sources.
LoopBack is built on top of express. You can use express routing and middleware with LoopBack as is.
Express allows you to expose HTTP endpoints as APIs but it doesn't facilitate the quest to build/aggregate/protect/document APIs that interacts with various backend systems, such as DBs, Cloud services, and internal REST/SOAP APIs. LoopBack is positioned to be a fully-fledged API server with SDKs for JS, iOS, and Android.
2. We allow you to execute native query using
dataSource.connector.query(query, params, cb). We're considering to promote it to dataSource level and fully document it.
LoopBack is open source. The repos are public and the node modules have been published to NPM registry. As a Node developer, you can definitely use/hack it as usual.
LoopBack is part of the StrongLoop suite distribution too. That's where you will get an integrated solution (with StrongNode & StrongOps) and commercial supports.