Could it be possible to add the chord type Major b5? (which is a major triad with a diminished fifth: 1, 3, b5 or 1, 3, #4)
There's already a 7b5 chord type, but the Major b5 (without 7th) can open a wide range of new chords (when having different bass notes) that are not possible with the existing chord types in IRP. These chords are widely used in flamenco, fusion and modern jazz.
This new chord type could actually replace some redundant chord types in the existing library (∆7 = ∆, m7b5 = Ø = Ø7, etc...)