Alan Turing's contributions to science and the war time effort were immense, and immeasurable. However, granting a pardon to him and him alone won't mean much. He was guilty. The law which he broke was draconian, no doubts about it, but it was the law at that time. I do not think he was the only Briton who was oppressed because of that particular law.

If there is a pardon, and there should be one, it should be granted to everyone who was convicted under that law.