AndreasC said:
While perhaps someone may find all these opinions interesting, I would prefer if someone answered the actual question rather than attacking its premises...
In my opinion, the greatest of his papers is his PhD thesis, A New Determination of Molecular Dimensions.
http://www.zhenzhubay.com/zzw/upload/up/2/378598b.pdf
It is the least known of his 1905 miracle papers. Yet, it is the most cited in professional literature. Why? For the first time, it put the atomic hypothesis to the ultimate test of any theory - experiment. Also, it had surprising applications.
For an overview of why I consider it so great, see:
https://arxiv.org/abs/physics/0504201
It must be remembered that his papers on Relativity and the Photoelectric effect, while revolutionary, were different from the atomic hypothesis, which had been around for some time. They took time to be accepted; initially, many still doubted them. His PhD paper put the nail in the coffin of the doubters on the existence of atoms.
Interestingly, it was at first rejected as too short. He added a sentence, and it was accepted. Throughout Einstein's early career, we see he was only 'appreciated' by some of the most outstanding scientists of his time, like Plank, who quickly became his friend. Even the great Poincare had 'issues' with Einstein. He had discovered much of SR but could not put it on the firm foundation Einstein did. When Minkowski gave it his geometrical foundation, Poincare should have seen it immediately. I do not know what Poincare made of Minkowski's work, or even if he knew of it, but there is no doubt he would have grasped the math immediately.
Thanks
Bill