Add some checks for container usertypes that masquerade as convertible from tables
Make sure shared_ptr-like types that are copyable are returned directly (but do not do this for move-only types)
Reduce compile-times by removing lambda shenanigans and moving data that is already serialized into runtime systems to runtime
Fix bugs with precedence ordering related to index and new_index
Prepare to add 20000 more if constexpr to reduce compile-times even further.