I am coming to a similar conclusion with my band. ... I know ultimatums are not the best idea but I have sunk to much money and time in a band run by people who are satisfied with mediocrity. Any band maintenance tips would be much appreciated.
Honestly, this is why I quit the band I was in last spring/summer. Great guys, fun music, but there was no consistency. I need a regular jam, or I get all cranky. Sure, I get that they had been playing these songs for years, but I haven't and I needed the rehearsal to work out breakdowns with the drummer, etc. But it was less that than the weekly "We jammin?" "Let me check" days go by "oh, drummer has work, guitard is going camping, etc"
Drove me nuts.
Not marching band, but former military, similar approaches I'm sure