A Blueprint prototype is not automatically bad architecture. The real warning signs are duplicated rules, unclear ownership, circular dependencies, fragile references, and logic that becomes impossible to test without reproducing an entire gameplay sequence.
Move rules, not every visible detail
Core state, validation, damage rules, inventory operations, save structures, and reusable components are strong candidates for C++. Designer-controlled content can still come from Data Assets, exposed properties, curves, and editor configuration.
Migration should preserve working content
A proper migration does not throw away animations, levels, or authored assets. It creates a native foundation beneath them, then moves one responsibility at a time while keeping the project playable.
The useful outcome
The result should be easier to extend, easier to debug, and safer to update—not merely “more C++.”