Koch was the type of Democrat I could have a conversation with. He was not anti-American like today's Democrats. He was for America and for our military and our fight for freedom against totalitarian aggression abroad, in the mold of JFK, Truman, LBJ, etc.
His endorsement of Bush and McCain attests to his love of country and ahavat yisrael, and I enjoyed his political commentary and desire to stamp out corruption in local politics.
His memory should be for a blessing.
That being said, I don't think the "daat torah" would permit watching his funeral. R' Soloveitchik didn't allow people to watch Kennedy's funeral mass on television, since he saw this as an extension of the prohibition on entering a church. Likewise, I don't think one could find a heter for viewing a Reform service on television.
Especially considering that Temple Emanu El is a holdout of Classical Reform.
Be kitzur, American Reform in the 1880s totally stopped any ritual observance (see the Pittsburgh Platform of 1885), since they denied the binding nature of mitzvot.
This was unlike the earliest German maskilim, like Chorin, who employed tradition and were more or less halakhic/neolog. Certainly, they used certain aesthetics which were not problematic in the sanctuary (like Geneva robes, choirs, vernacular, learned sermons, etc. which the Hirschians and early American Orthodox used), but their theology urged little more than an Ethical Monotheism devoid of anything uniquely Jewish.
Thus, the desire to emulate Christian churches in aesthetic.
The Reform environment I was raised in was more like "Reformadox." Nowadays, many Reform Jews individually (my household incluced) observe kashrut, shabbat, tefillin, etc, and more closely resembles Reconstructionism, which is itself a liberal offshoot of Conservative Judaism and places an emphasis on observing what they view as folkways. Reform Jews participate in non-denominational yeshivot like Hadar and Pardes, where Orthodox-trained and Halakhic old-style JTS faculty train them in making a leining on Gemara/Rashi/Tosafot/rishonim, etc. Hebrew Union College employs Prof. Michael Chernick, who has semicha from RIETS and is active in the left-wing Modern Orthodox sector, and he teaches seminar courses in "Talmud with Rishonim." One of his syllabi online shows that Reform rabbinical students in his class learned perek slishi of Sanhedrin with Ritva, Tosfos Rid, Ramban, Meiri, and Rashba.
Emanu-El is a holdout of the olden days resisting this otherwise positive development, and therefore is problematic.