When we check the hadith literature we may find out that commentators in first place focussed on the two sahihs and al-Muwatta' which for which one may find much more than ten commentaries, when we move to the so called sunan-books (sunan ibn Majah, abi Dawood, an-Nasa'i) and Jami' at-Tirmdhi we may find less commentaries and often the commentators rely on comments of either the sahihs or al-Muwatta'. However I think that one of both sunan books of an-Nasa'i we find out that the book which was commented is rather his sunan as-Sughra (the small sunnan) than as-Sunnan al_Kubra (the big sunnan).

Of course many efforts and books have surely disappeared! So we may miss a lot of the efforts of early scholars.

My question is are there any known commentaries on other books (Examples to make a kind of focus) like:

 - Musnad Ahmad.
 - Musnad ad-Daraqotni

which would complete the 9 sunnan books and

 - At-Tabarnis three encyclopaedias (al-Majma' as-Saghir, al-Majma' al-Awsat, al-Majma' al-Kabir)
 - Musnad al-Bazzar.
 - al-Mustadrak of al-Hakim
 - as-Sunan al-Kubra of al-Bayhaqi

which might also be rather known. There of course much more books which are more or less known like the musnad's of a-Shafi'i and abu Hanifa.