I agree with most of this, but there are several things that I do not agree with. Even though Japan has apologized many times for many issues, many people do not see these apologies as acceptable because of the attitude of Japan's society and government.
In the same way that a person can apologize without actually meaning it, many people believe that Japan's apologies have been more or less hollow. Now, I believe that there is true remorse and regret in Japan, but at the same time, there is still an element of indifference, self-victimization, and denial.
A good apology isn't just words, but also actions, and I don't mean just monetary compensation. Using other nations' apologies for various historic grievances further highlight Japan's unsatisfactory apologies. In the US, for example, slavery and civil rights for black people were massive human rights violations in the past. The US government has apologized many times, and for the most part, Americans have accepted these things to be products of a time far more barbaric than ours. What makes the US's apologies different than Japan's is that the victims can accept it. They accepted it because America's society and government (for the most part) did not send ambiguous messages and clearly moved towards equality.
Looking at Japan, however, one can understand why some victims of Japan's atrocities have not accepted the country's apologies. Controversial events, such as Yasukuni Shrine visits and the textbook revisions, combined with offensive comments made by prominent politicians, have smeared the apologies that it had made. Imagine if politicians in the US visited the symbolic graves of KKK members and approved textbooks that whitewashed slavery; most of America would not stand for such insensitive and damaging behavior.
I believe that the current generation of Japanese people have no responsibility for the atrocities of World War II, but knowledge and compassion of their historic wrongs are essential to the mending process (and likewise for citizens of the victimized countries). I also believe that the path towards reconciliation can be started only by Japan, and this involves unambiguous apologies that reflect Japanese government and society that the victims of Japan's atrocities can accept.