Almost all API calls are for features on Steemit. The API has to be more general. There are a lot of queries that are important for other apps on Steem that aren't possible at the moment.
Appbase has many API improvements. One of them is a new database_api that is de-coupled from Condenser (steemit.com). It allows for paginated query of all database objects by all orderings the blockchain uses.
It may not be all of the information you need, but it is substantially more than what is currently available.