Sickle cell is a mutation caused by the loss of information. It is not what evolution needs. It is not only lethal in the homozygotic state, there is evidence that it is a compromising factor in the immune system in the heterozygotic state. It is not a beneficial mutation at all in the general sense and only has a 'SIDE effect' of malarial resistance, and not always to a high degree! So let's call it what it really is -- a possibly lethal mutation that simply, via the loss of information, does not allow malaria the hold it needs in the body.
Since, also, we have people today with long legs and short legs, all of which are of an entirely different hip structure from the primates, the idea of evolution from short legs to long legs is only laughable.
You made the snide remark that God did not do a very good job in designing the human race. Excuse me? You are judging God? I think that, considering that our bodies seem to survive most of the insults we throw at them, He didn't do a half bad job! Please remember, by the way, that men were created perfect physically. What we have today is a result of what we have done to ourselves. We have gone downhill, not uphill.
My point about the virus was that it is still a virus. Yeast is still yeast. Bears are still bears. E.coli is still E.coli. Ferns are still ferns. The list is rather exhaustive. "Beneficial" or other mutations change nothing in terms of the identity of the organism in terms of its kind.