All great recommendations...I've placed a few orders on Amazon...thanx a ton!!
Another work that is clearly upbeat is the Mozart Piano Concerto No. 21. The cadenzas were not written down because Mozart did not need to do so. So, there will be sections where the "gap is filled" by a lesser musician and the break in "flow and transition" is rather obvious.
Of the performances I've heard, I have two that have latched on to me.
One is by Pollini. Probably the biggest insight I got from this was a part of the development section basically does away with the distinction of one hand having the melody and the other the accompaniment. The whole interaction is the "melody" starting at 7:53.
The other performances involve Ronald Brautigam. Brautigam is part of the "HIP" school, which is the aforesaid academic movement within classical circles(other proponents being the likes of Roger Norrington and Robert Levin) which adopt certain rules for performance practice. Though as necessary movement, it being more academic rule than just "play the music" can result in unmusical idiosyncrasies. The fast movements are usually enhanced but slow movements can sometimes feel a bit "rushed".
This recording has the features of no vibrato in the orchestra and a speedier tempo for the Andante. But because it is the instruments from Mozart's time, there is more balance and audibility from all instruments involved.
https://www.youtube.com/watch?v=zXHc5sxUMBQ
He does things a bit different live and on a modern grand; the Andante is slowed down to a more conventional pace.
In addition, Geza Anda's version is worth a listen simply because he has a lot of musicality.