In my opinion, one most know the following:
1) One day, Vladimir Horowitz got the bright idea in the middle of an interview to state that Muzio Clementi was a far superior composer to Mozart. From then on, everybody starting learning music that had, prior that time, rarely ever been assigned to a student by the average piano teacher.
This, coming from a man (Clementi), who exclusively spent his last years as a very successful piano salesman.
2) The pianofortes of his day were solid wood sound board pianos, which could/can in no way produce the volume, tone, or nuance of a modern grand. In terms of velocity, the pianofortes played/play like lightening.
Therefore, in terms of interpretations, in my opinion, it is at most an improvisational transcription to play these pieces. What about Mozart?: more to come on that subject later.