You could bring it up with the whole band in the context of a set list discussion. I don't believe most audiences like multipe extended changes and delays. The best bands (to me) always have great, tight transitions between songs which are well planned in advance to minimize dead space. We plan for that and rehearse it extensively. You can suggest that changing out drummers is just too time consuming and takes away from the continuity of a set. Possibly you can get some audience feedback from a trusted fan to support this. Just a suggestion FWIW.
I am 3 instrument proficient but in my current gig I put all my energy into one....the bass and it pays off in terms of tightness and proficiency and also writing of new material...all the bass lines are mine. Our drummer has 40+ years gigging experience, and while I could play as well or better than he can on some songs, I would never thing of doing so because as a band it sounds best with him in the chair and me standing up. I think you are on the right track encouraging him on the guitar and also if he sings or wants to sing harmony, focusing on that with one instrument is a better option.
I am 3 instrument proficient but in my current gig I put all my energy into one....the bass and it pays off in terms of tightness and proficiency and also writing of new material...all the bass lines are mine. Our drummer has 40+ years gigging experience, and while I could play as well or better than he can on some songs, I would never thing of doing so because as a band it sounds best with him in the chair and me standing up. I think you are on the right track encouraging him on the guitar and also if he sings or wants to sing harmony, focusing on that with one instrument is a better option.
