There's two strains of thought here, there's people judging him in historical context and there's people judging him by the standards we would hold a modern person to. This is not something that's automatically wrong, just something people should be aware that they're doing.
As far as historical context goes, he was a talented administrative and tactical mind; his military tactics were to some extent predictable once people became adjusted to them, but that does not decrease their general levels of success. He was able to wash away a brutal regime and replace it with a functioning one that did not victimise its own subjects. He produced a legal code that lasted well after his death and that continues to be the foundation of modern law in many states. He was obsessed with glory on the battlefield and being at the head of it, but unlike the rest of his peers he was able to back up his rhetoric. He was ambitious in a time that produced ambitious men. And by ancient standards he was effective, relatively humble, and achieved great things.
As far as I would personally judge a human being, he was vainglorious, childish and neurotic. He thought nothing of causing wars that devastated the manpower of France, and those of foreign countries, and the destruction caused to civilians. He helped codify the modern image of the nation-state, which in turn is responsible for the use of nationalism in the cause of excess, cultural emasculation, and wholesale slaughter. He was a poor lover (which doesn't make him morally bad but is something I would still find objectionable), stubborn, and scheming. He was unable to adjust to what would be some of the most important social and technological changes of the next century, he was without natural loyalties except to himself and perhaps to France, and all in all he was egotistical in a way that most would find horrifying.
As a historian, he is generally an admirable figure. But there are few historically admirable figures that any of us would actually like.
