What in your opinion or experience is the minimum aperture necessary
for satisfying views of globular clusters and galaxies?


Hmm . . . you did specify *minimum* didn't you? When asked in that
manner my reply would be:

The smallest telescope I happen to own -- 80mm. I find satisfaction
in finding and identifying objects with small telescopes. Any visible
details that might greet me from within an object would be looked upon
as 'icing on the cake'.

It is satisfying to find Globulars and Galaxies in a smaller scope but it
seemed to me that the issue was about "viewing" them rather than finding
them...

jon