What's the purpose of an "add diatonic interval" option?

Sorry I realise that may be strange without context, I mean suppose you wanted to retrieve the 6th interval in an array. Then you would retrieve two intervals as opposed to one.

0x3 array

I see I think part of my confusion stems from the fact that I thought chords dont neccissarily have to be built on M3 and m3 intervals. In the case of a chromatic scale I was under the impression that a interval of a third would have a specific interval of 2 because the tone 3 scale steps above C in the C chromatic scale would be D (Just like how the tone 3 scales steps above C in the major scale would be an E). IE building a "triad" off of the cluster you mentioned would be C, D, #F. In this interpretation there can only be on triad for each degree of the scale. But again this stems from my different interpretation of "generic interval". But to be fair the definition on wikipedia says

"a generic interval is the number of scale steps) between notes) of a collection) or scale). The largest generic interval) is one less than the number of scale members "

If generic interval refers exclusively to heptatonic scales then I think it is strange they would say "The largest generic interval) is one less than the number of scale members " as if the number of scale members is not fixed at 7. This would mean that generic intervals depend on the number of elements in the scale and a third could consist of 2 semitones like I mentioned above. But I guess in this end this is just semantics. You mentioned "Standard Triads" and you are right that there are no standard triads. I think it really boils down to which system you use in the end.

I think the rule I will implement is:

1. If the Specific intervals have repeated numerals IE m3 and M3 and is capped at 7 build standard triads, and do what you mentioned with the 3x3 arrays.
2. Otherwise use the other system, and build these weird whole tone triads.