From what I've seen, the power of the detective role is directly proportional to the amount of out of thread communication in a game.

I play on Realms Beyond Net, and we allow no out of thread communication (except masons and mafia). So it's typical for "seers" aka detectives to sit on several days worth of data lest they reveal too early and get killed off.

But even there we've started to debate the power of the Seer roles. Towns seem to win games with true seers and lose games with no seers or limited seers.