ADDDITIONAL ACCOMPANIMENT
“It sounds good with the vocals and the acoustic guitar, but I think now we should add some drums!.” - Ringo to Paul after the recording of the song Yesterday.
Why let your accordion carry the load all by itself? One obvious add-on is your voice. Most people can sing somewhat. If you just can't, so be it. But, if you can, you should consider singing on some songs. But, “I can't sing and play at the same time”! Address this problem in the same fashion as playing a difficult passage – slow down, take a piece at a time, and practice repetitively. In addition, simplify the accordion part until you find that you can play and sing simultaneously – then, you can increase the degree of difficulty of the accompaniment.
Use of added electronics such as a rhythm machine increase the robustness of your arrangements.
USING THE ACCORDION'S CAPABILITIES