To call Sehwag a flat track bully is a bit unfair, even in todays era of relatively flat pitches. If Viv Richards had been around today people would have called him a flat track bully because he would have smashed Bangladesh for about 500 in a day.
Sehwag averages just short of 60 in Australia including 2 centuries and 3 fifties there, this is in an era where the Aussie bowling attack had Shane Warne, Glenn McGrath and support bowlers like Lee, Gillespie etc in it, so he's not only a demolisher of crap attacks on flat wickets. Matthew Hayden gets the same accusation.
Yes Sehwag and Hayden are not quite in the league of Lara, Richards, Tendulkar etc, but they are certainly greats.
India has produced a crop of batsmen in the modern era who I think will be remembered like the West Indian fast bowling dynasty of the 70s and 80s, one after another great comes along, Tendulkar, Dravid, Ganguly, Sehwag. The underrated one who was dropped too early was Vinod Kambli who I thought looked great in the early 90s but they just seemed to fall out with him.
My personal favourite though, Lancashire bias aside, is VVS Laxman, best player of spin bowlers ever, Warne, Murali, Saqlain in his day, none of them have ever given Laxman problems, he's probably the only batsman around that can be said about.