Reckon he's a bit underrated round these parts. Probably played on a year too long in the end, with hindsight, and I think that's affected how he's seen. Was a massively important player in tests and ODIs for a long time, after waiting more than 100 FC matches to get a Test. Probably the best batsman to watch I've seen, and an extraordinary fielder, possibly the best slips fielder ever.
Steve as a brother undoubtedly affects how he's viewed, as did the nature of his flaws - eg looking soft when he gets out, rarely going on for big tons. But all batsmen have flaws, and those happen to be two that people judge harshly, as opposed to some others.