At first it sounded unusual slow to me but it is not impossible slow. Double the tempo would be too fast, maybe a slightly faster tempo would easen to pecept the melody still as a line and not as single notes.
I think Chris is right, especially for those slow pieces should be every note there.
I don't think it is easy to play that calm and soft. In fact, very soft and nevertheless evenly playing shows who has truely relaxed hands and fingers combined with sensitive hearing and who has not, so I think (of course also a question of an appropriate piano too). You have a VERY good keytouch, combined with good technique, what your Chopin Etudes show. You are still young and will go very far, that's for sure!
There's a fine line between a very softly played tone and no tone at all. (Or I could be an artsy-fartsy smartass and say it was a ppppppppp.)
You are so right - much too often I fall behind the line, and the intended pp turns into nothing, because the hammer pegs out on the way to the string...