Review and unify API calls

[ethanfrey]

Part of #751
Requires #752, #753, #754, #755

• Revisit the various method calls that were created as part of the implementation of the other PRs
• Modify it as needed to make it as clear/readable as possible
• Consider if a crypto feature flag makes sense. (Do unit tests of non-crypto contracts take much longer to compile/run?)
• Update tests

[ethanfrey]

I guess this has already been done?
Or is there anything left?

[webmaster128]

I am not aware of anything specifric enough to do right now. Insights will come with use cases. But those are better tracked in specific tickets.