'Kiusupunn' said she will leave out the back cables in next cardy because they don't hold well.
So I did a little trial :
Couldn't keep myself ;) and made a little tutorial as well : Three needle bind off.
But I didn't like the look of the seam either so riped it open again and will go for back cables.
Already then had idea to add cable.
Here it is :
I casted on 7 stitches (1extra for sewing),knitted long cable and sewed it to sleeve.
EDIT: Great tutorial from olgajazzzy how to connect cable to sleeve's live stitches.