It might sound like a worthy goal to have a one tool does all utility. But in light of the variety of functions one might want to perform at one time or another I am not so sure. Such a utility would almost inevitably be accused of "feature bloat" and likely would become too cumbersome to be helpful.
For volume maintenance and repair (a more accurate term than disk repair) IMHO any one of the three tools already mentioned, Diskwarrior, Techtool Pro, and Drive Genius will get the job done and done well. Each has its advantages and cadre of ardent advocates. Each offers a 30 day try before you buy. Which one you choose is largely a matter of personal taste. I had TechTool Pro before either of the other two were released and use it out of habit as much as anything. I got Drive Genius after the local Genius Desk used it and I was impressed with its speed compared to the other two.
For general "housekeeping" I have OnyX, Cocktial, and TinkerTool System and use all three. If I had to choose only one of the three it would probably be TinkerTool System because of my long history with TinkierTool and because it has some unique features not supported by either of the others.
MacPilot is unique in offering access to roughly 1,000 "hidden" configuration items in OS X and the OS X applications. I could easily get along without MacPilot, but it has been nice to have. If I think about adding all that to another application would be too likely to create GUI overload.
I have long been a fan of CleanApp for thoroughly removing all trces of a deleted application from the system, and there are other similar apps out there. I would not need CleanApp nearly as much if it weren't for my penchant for trying out new apps or perhaps I should be more choosey in what apps I install and I wouldn't need to remove so many.
With the exception of the volume maintenance utilities there is little that cannot be done from Terminal using the same Unix commands the various utilities use to perform their functions. The various utilities are in fact just a convenience. — Boy do I love convenience!