Hey @Polly
This should be entirely possible - with some caveats.
The Speckle Server can deliver data partially according to the criteria you define. This is because there is full support for GraphQL querying - designed for this scenario.
However, this is limited to making queries filtering to data properties.
The tricky part would only be what you define as relevant content. I haven’t explored making the queries filter to a geometric location based on a bounding box, but it may be possible with compound filters TBD.
I may give this a play, in the meantime, because you have full access to the Speckle Core operations, take a look at some other examples of commit data filtering:
https://speckle.guide/dev/server-graphql-api.html#advanced-queries