The three decisions ring true, and hybrid search is the one teams skip longest, dense vectors alone miss product codes and acronyms that a BM25 pass catches instantly. The line I'd underline is building a retrieval eval set early, without real questions mapped to correct source docs you're tuning blind and regressions surface as user tickets in week three. Do you score retrieval separately from the final answer, so you can tell a retrieval miss from a generation miss?