i was never super impressed by lecavalier, though like everyone else i was certainly dazzled by him on occasion. during the 2004 world cup, he was good, but i don't think it was an especially memorable performance. i think it was more the case of a guy who had a good tournament and scored one big time memorable goal. i do, however, think he was a guy that the world wanted to make "happen," and so when he succeeded for that brief stretch, the world went out of its way to treat him like he had made it to that truly elite iginla/thornton level when really he was a step below.
i also think lecavalier was a very linemate-dependent player. he and vinny prospal had something really special, and you can see that he has his breakthrough '03 season with prospal (first line was modin/richards/MSL) then drops 12 points when prospal bolts for anaheim, then rebounds in '06 when prospal comes back. he peaks in '07 and '08, when torts stacks his top line with lecavalier between two-time art ross winner MSL and prospal, two excellent playmaking wingers. probably also worth noting that he was outscored by his playmaking winger in '03 (prospal, albeit by only a point), '04 (stillman), and '06 (prospal again).
i can't speak to bobby smith's play with minnesota the first time around, though by all accounts he was slick and not as physical as you'd like for a guy that size so probably very similar to lecavalier, but in montreal smith was a very good defensive player, albeit not taking on the responsibilities that carbonneau and skrudland did on those teams, and in his second go-around in minnesota he was excellent on a shutdown line with gaetan duchesne and stew gavin. (sidenote: one reason montreal was so dominant in the late 80s with no stars at forward? with three big huge guys at center ice, smith, carbo, and skrudland, there was only one team that could get the puck from them off the dot... that team had gilmour, and two other giants in nieuwendyk and otto.) lecavalier i don't think was ever anything defensively.
i'd be more inclined to compare bobby smith to someone like anze kopitar.