Critique and Advice; the treadmill of adventuring.

I think author inserts (ala homestuck) are generally more acceptable than self-inserts, if that makes sense. But still only when the story is already kind of silly and meta.

I agree. But most 'author' inserts tend to be an exaggerated version of the creator, or even a different character entirely (or an assumption of who the author is). Good ones are more like pen-handles ala 'Lemony Snicket' or something. Those can be pretty fun.