I like him a lot. I think his batting's slightly under-rated: for a guy with a lowish test average, he played numerous match-winning innings, often in circumstances that were far from easy. There's a piece somewhere in the CW archives about all that from soon after he retired in May or June 2004.
As a captain, I think he's slightly over-rated, certainly in terms of his actual results. The idea that England were completely hopeless when he took over the reins isn't completely supported by the fact that they'd beaten SA the previous summer, and even less by his team's defeat at home to NZ in his first series. The subsequent loss in SA was fair enough, but his side then lost the first test at home to WI by an innings, which no self-respecting team did even then. People forget that the miracle of Lord's 2000 was overseen by Stewart, as Hussain was injured for that test, and thereafter WI did what they did everywhere for the rest of that series. All that being said, his wins in Pakistan & Sri Lanka the following winter were outstanding performances, and numerous injuries in 2001 meant the side never got going at home to an Australian side who were pretty much at the peak of their powers. Thereafter, his captaincy seemed dominated by fear, culminating in the daft decision to insert Aus in the first Ashes test in 2003/03. By then, his approach to man-management was looking counter productive, especially with some of the bowlers.
So not our finest ever captain imo, although obviously there were notable achievements, especially in the subcontinent.