Oh you'll never make everyone happy, someone will always complain about being short-changed, so best you don't try. I don't know how many times I've heard established fans say something like, 'A panel on such-and-such? But we've all seen it done before at other cons, we know all about that!'

Which ignores the fact that there will always be a percentage of newer fans who haven't been around for the last decade and so haven't seen this panel topic ever! Naturally you don't aim the entire program at the newbies, but I guess that's what you're saying about the tricky problems of balance.

I guess what I'm saying is, so long as at the end of the day you know you've done the absolute best job you could to make it a varied and interesting program for everyone, have taken on board advice and criticism, and have tried to take note of any mistakes so you don't repeat them in the future, that's what matters.