A chord survey Ab+2, Bb +1, C 0, D -1

Here you can find where   the major triads (in yellow) are and in which setup the chord (or single tone)  is highest in pitch. 
The dark color means that you also can get a nice (not pure) minor 7th in addition. 
(Comparing must be done only vertical)

And here is the minor triads available :

And at last  the sus4 chords. The darker color means that you also can play sus2.  Example : In C 0  you can play the melody line F-E-D-E in between the fifth (C-G) pure.

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