Jack o' Diamonds wrote in Bach Cello Suite No. 1 Prelude:
Prefer Duarte's drop D transcription especially his minor 3rd extravaganza from bar 37 onwards.
My choice is keys directly relates to how I want the piece to be perceived. To me, placing the piece in D major simply makes it 'wimpy' sounding. And was one of the major factors of what I never got excited to learn the piece before. Sure, you are able to extend the lower range, add lots of counter lines to the piece and make it more of a lute/guitar performance. For some performers, this is what they want and play the piece quite effectively that way (note Barrueco's recording of this piece). Those extra basses and at times completely new contrapuntal lines certainly fill in the space left by placing the melody a 5th higher then the original pitch.
Using A major as the key places the melody in the same range as the original. Instead of a 5th higher and playing the melody mostly on the 2nd and 1st string, A major places the melody on the 2nd and 3 string mostly. Since the cello's range (string wise) is comparable to the guitar from strings 6-3 I find that A major fits to bring out the richness of the suite. Playing on the 1st string is equivalent to playing in the higher positions on the cello, however the melody is a fairly low register. I tune the low 6th string to D to reach the lower notes towards the middle of the piece. In the original cello version there's a 5th below the G (low C - the instrument's lowest pitch). With the D as the 6th string, I'm able to recreate the same movement from A down to the low D.
This transcription is more able bringing out the brilliance of the cello writing, rather then adding supportive lines to fill out the range. The different versions in D major are great, and serve a certain purpose. However, for me it's not how I envision the piece, which is why I chose to put it in A major.
As for the minor 3rd progression chromatically up the scale at the end of the piece, I must admit I tried something similar in my initial version. It make the section far too complicated, and I found I was able to achieve the same drama with being able to get a fat rest stroke sound and the range that the melody was placed (which is much lower then the D major versions). It would have been nice to add something like that in, but it was a compromise I had to make.
Paul McGuffin wrote in Bach Cello Suite No. 1 Prelude:
... but I like your phrasing. Nice hold there, in the middel part. Most player run through the piece like a house on fire.
There are some great harmonic changes during the middle section of this piece, all under an E pedal. I've heard by several musicians that Bach was the 'jazzer' of his time, and this section certainly reminds me what Jazz players do, outlining chord changes through melodic passages of scales and arpeggios. To me, it's a great moment in the piece.