Bass part in midi styles is not correct. For clarity’s sake, I provide some proof, here.

Please note that
I Turned off Natural arrangement: never, even if... Preferences, Arrangement
Bass part: i expressly turned off natural arrangement or embellishment
Overrides: i turned off “simple bass”

https://www.dropbox.com/s/s1r7f68j8uiky7d/BASSPARTBRUSH300.pdf?dl=0

https://www.dropbox.com/s/3mia8zswdzmdo30/BRUBECKBALLADBASSPART.pdf?dl=0

As to the choice of chords:
They are provided in the chord builder
13b9 is common
mMaj7 is the Billy Strayhorn chord “par excellence”
m9b5 is the Bill Evans chord
Susb9 is the phrygian chord (read: kenny Wheeler, Branford Marsalis, Brecker)


Biab, Kontakt, Sampletank and lots of nice libraries, from Fluffy audio to Abbey Road drums.
Check out these great contemporary Jazz Styles: www.jazzstylezz.com