Someone posted his rules for classical concerts if they were done entirely to his tastes, and Lisa Irontongue endorsed them.
Not I; I'd make several things differently.
Short concerts should be held only to fit short time periods. 45-minute lunch concerts near workplaces (bag lunches welcome) are a great idea. Otherwise, a concert should be long enough to make traveling to it a worthwhile time investment.
No soloists whose names get printed in bigger type than that of the composer they're playing.
The average concert (and by "average" I mean that departures from this rule are welcome, but should be balanced by other concerts departing in the other direction) should contain 3 works, of which one should be an old favorite that everybody knows, one should be a little-known favorite of mine that only I know (hey, these are my rules), and one should be unknown, preferably fairly new.
About 50% of all music not at "early music" concerts should date from since 1900.
No premieres. Every new work should be receiving its second or third performance. When a new work comes to the stage, somehow the premiere will have already happened. (This is my only rule requiring magic.)
Talks about the music belong at pre-concert lectures, and should not duplicate the program notes. Performers during the concert itself should not be permitted to try to explain the music.
If you play pops, rehearse it like you would the finest symphony; don't toss it off casually.