Hey man, all do respect, but when you run into issues with C++ you should try googling why things are that way. C++ is still pretty well on the cutting edge of programming languages provided you’re using near the latest version. You’re really comparing apples and oranges comparing compiled languages (C++) to JIT languages (C#). Your example from earlier (header files being useless), really shows your lack of understanding. Header files exist to separate implementation from definition, essentially like a glossary for the compiler. In C# because it’s compiling to MIL it stores that data in the metadata generated beforehand that the JIT compiler can use at runtime. C++ compiling would be hell without the separation.
You don’t need to use header files in C++, it’s just not really in your best interest to avoid them.
Unreal’s UObject system is already a system for intermingling managed and unmanaged code. You’re asking for a that already exists in the engine.