Omar was ill equipped to do either. In short, he was a glorified scout who fell victim to the Peter Principle. The organization was a total mess under his watch. Perhaps you've forgotten Tony Bernazard?
But it's interesting you bring up RA Dickey. In an interview this past season. Omar admitted that the only reason he signed RA was that he thought he'd made a good coach some day and wanted him in the organization. He said he never would have thought he'd ever be this good.
Still, he gets kudos for thinking in those terms. Let's not forget he also had success with Jose Valentin and Fernando Tatis. Unfortunately, it was his dismantling of the bullpen after the 2006 team that led to the team's demise. Then the dominoes began to fall.
Yes, Omar takes a lot of heat for the team's failings and rightfully so. But guess what? Now it's Sandy's turn to be raked over the coals. What's fair is fair.