Does Time To Throw for a QB allow all plays or only the ones when he's within the tackle box? I was always wary if it included scramble plays and if so, that's more of an indictment of the O-line than praise even though the time to throw is longer.
If interceptions are 55% luck and that's too much to allow for turnover ratio, by extension, interceptions largely don't matter as well (forget about the TDs and ratio part).
But I don't entirely buy that. Good QBs historically throw fewer INTs than not so good QBs. Is it the be-all-end-all? No, but it matters in context.