To be honest, I have to disagree here. Looking at his tenure, I would say, under the Prince we do have a 'long term future' - ie: we'll always be fine and OK, and won't go into administration. OK, so we might not build on our PL Promotion, we might get relegated, we may have to accept years in the Championship, but I'm fairly confident - if I base my response on what I think the 'long term future' is, Sheffield United is in relatively, perhaps frustrating and boring, safe hands.
If by long term future, you mean someone who will pump millions into the club, buy expensive players and push for a top PL finish, then you're right - he will never do that. But, that's short term future, or a gamble perhaps.