A lot has been written abt. Rabbi Sacks since his passing. I will add my two cents [b/c of the financial crunch I won't offer more:-)]. .
I think that his works should be studied and critically analyzed to see which of his ideas truly reflect the thrust of our tradition. Those that do - AWE-SOME! If there are ideas that run counter to our core beliefs, then this must be recognized. That applies to ANYONE. It is just more significant to make the point regarding him b/c, as he often used the word "radical", to describe ideas he espoused. One of his books is even called "Radical Then, Radical Now".
Of course it goes w/o saying that regardless - I am saddened, together w/ millions of others, by his loss.
The main point I want to make is the following:
The pasuk says -
וּשְׁמַרְתֶּם וַעֲשִׂיתֶם כִּי הִוא חָכְמַתְכֶם וּבִינַתְכֶם לְעֵינֵי הָעַמִּים אֲשֶׁר יִשְׁמְעוּן אֵת כָּל הַחֻקִּים הָאֵלֶּה וְאָמְרוּ רַק עַם חָכָם וְנָבוֹן הַגּוֹי הַגָּדוֹל הַזֶּה.
When Goyim hear about the Torah they should exclaim "WHAT A WISE NATION THE JEWS ARE!!!" It is safe to say that there is not one person alive who comes even close to him in presenting the Torah and Judaism to the world in such a way that makes the world appreciate its wisdom and that of the Jews. And THAT - is a huge loss.
All we can do is try to make up for it and live lives that make all humanity appreciate the wisdom of our people and Torah. I don't think that I am going out on a limb when I say that we often fall short of the mark. וד"ל.
There is a lot more to say abt. the Late Lord [seems theologically problematic to say that but you know what I mean] and you can read more abt. him elsewhere.