To get a clearer picture of this issue, it'd help to know:

• Which packages (or, more precisely, classes) are needed actually?
• What is the need / use case for accessing these types?

Based on that we can move forward and decide for each use case:

• Is there already a public API/SPI which can be used?
• If there is none, how could a new API/SPI look like? Should it be just the currently used internal type or a more generic / easy to use / limited etc. variant?