I listened to the Book I pair. Overall, the main item that could use more work is the rhythm, particularly tempo retention and precision. Much of this is just sounding rather flabby and inexact to my ears. I think the fugue is better than the prelude and nicely voiced in places (though I know I have a different definition of voicing than certain people on here), but both pieces (particularly the prelude) need to be more exact.
Prelude: I find this a relatively straightforward piece, but arguably one of the more difficult preludes in Book I from the purely pyrotechnical standpoint. First, and this is partly a musical thing, where's the wonderful pointed accent of that G on the downbeat? It's sounding like a wispy throwaway to me. Focusing more on that may make it easier to play the RH triplets. Technically, some of the triplets are ok, but others are quite uneven, particularly in the left hand (e.g., measures 9, 16). Some metronome work might help with that. Two other points are the pedalling and the overall tempo. I personally would say that pedalling, when employed in regular patterns, is a bit of a no-no in Bach (although, of course, in certain slow movements, for example, or where fugue voicing becomes impossible without it, it may become necessary and desirable). It's not gross here, but it's enough to produce an impression (for me) of haziness and flabbiness. This just seems like such a direct, masculine piece that needs only good, clean fingerwork, accenting, and confident musical intention to make its point. Regarding tempo, you seem to sag considerably starting around measure 12 and continuing to the end (also some hand asynchronicity). Not sure if it's intentional, but I personally wouldn't find it acceptable to do such a gross ritard that affects overall tempo. I like your subtle highlighting of that inner RH voice toward the end, but the syncing of the hands overall needs a bit of work for this ending.
Fugue: Some weak notes (some dubious-sounding notes in LH pattern in measures 25-26, for example, and other places in the second half) and smudging in places. Tempo sounds a bit fast for my taste, resulting again in a bit of an impression of unsureness/flabbiness. And there are still quite a few places that just need to be ironed out, such as rushings followed alternately by slowings down in the second half of the piece. IMO this all produces for the listener an effect of technical unsureness.
You can get there, I think. This just needs more technical preparation IMHO.
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