There's some important chords that aren't supported yet which would be very good to have :

sus maj7 or maj sus4 spelt... C,E,B or even C,E G,B

minMaj7b5 ...C, Eb F#, B
dim ........C , Eb, A
Maj7 add6 ..C, E ,G, A
min add9....C, Eb, G, D
min9#5......C, Eb, Ab, Bb


There's maybe more that others could add.

I wanted also to ask if it would be too difficult a job to allow people to add there own chords.
Or at least some kind of facilty for dropping one chord member the 3rd or 5th or 7th from a voicing would open up a lot of possibilities. Just trying to get some feedback from you on this.

It would be good if others bumped this thread and add their won thoughts too.

Regards

Alan