I saw the clip and I for one thought Laurence's take sounded fine.
We have to remember people, that the Silver Surfer is very much a demigod--a supremely powerful, celestial being. Therefore, his voice should reflect sheer power when necessary, as well as the humble mix of humanity when he's touched emotionally. A weaker, wispy voice to me would be mismatched for a being that wields such energy, because those of us who read the comics know that the Surfer can kick serious arse...with no apologies. His voice should be godlike, intimidating for first encounters, and this works in my opinion.
I think the whole reason some expect a softer, more feminine voice is because of the way the Surfer sounded on the old FF cartoon series from the 90's. I don't believe that's appropriate now.