The counterpoint sound is nice, good job!
I find there are a number of parallel octaves in the counterpoint. For example, in bar.2 beat 2 between tenor (blue) and bass (red), hidden octaves in bar 2 last beat to bar 3 between tenor (blue) and bass (red), parallel octaves in the last beat of bar 3 to bar 4 between tenor and bass. Subsequent appearances of the cell also repeat the parallel octaves.
Also the harmonic progression from bar 19 to 20, with C minor to C major, seems not smooth enough for me. Maybe adding intermediate f minor - G major progression will be smoother?
My "suggestion" is from someone old-schooled! Writing counterpoint, let alone triple invertible counterpoint is tedious and hard to do so! The sound is really well!