6+6-Accordion (Logicordion, "Pajano")

Button-Accordions provide the 12 Scales to be played on 3 Rows for the right hand, so that You only have to practice 3 Scales, the others work identically. But a melody runs in a serpentine in this system.
Piano-Accordion plays pretty Tunes in C-Major/a-Minor, but gets complicated in other scales.

6+6-Accordion is a pure synthesis between Piano- and Button-Accordion, and even between the different button accordion systems (B and C).
On a "6+6-Accordion" You play the 12 Scales with only 2 different patterns, depending on if the Scale's Base Key lies on the Upper or Lower Row.
Piano Teachers will miss their Scale-Unbalance. Unprejudiced People will love this Instrument because of the fact that each Interval in any Scale is played with identical finger patterns, which leads to much faster Practicing Progress than Piano-Accordion-Practicing.
What miracles can we expect from Virtuosi on this optimal Accordion!

It is hard to play a bass line with the left together with a melody on the right and additionally coordinate it with a good bellow movement, a means of expression that a piano doesn't have.
So the accordion should be built as simple as possible.

Bajan(without extra rows)-, 6+6- and Piano-Accordion
Serial Production of this Instrument would be easy: We only need 2 CAD-Models of the flat moulds instead of 6 as for the piano. Octave-Distance gets shorter, so that we can fit more than 4 Octaves on the space of formerly three and a half. This meets Classical Music Standards!