I've noticed a of artists draw themselves in crude caricatures or abstract figures compared to the rest of their art. Others, and it seems more common in amateurs, draw themselves with the same effort as everything else as idealized forms more attractive than their real selves. Does that say something about the artist or are simple self portraits just a byproduct of circumstances like not wanting to spend undue effort on illustrating commentary/afterwords outside the scope of a story?

uhm... 2GET

and I'll try to answer this later.

I think it has more to do with humbleness than anything else. If an artist were to make a self portrait with same amount of effort as everything else, it gives the impression that the artist thinks rather highly of him-/herself.

hmm . . . in a lot of shoujo manga, the artist will portray themselves as a cheerful but homely slacker in order to connect with the readers. The 14-yr-old female target-audience probably would feel intimidated reading side-columns by an artist who seems beautiful, talented, and successful.

I think it's somewhat that they are having a sense of humor about themselves. Plus if they draw themselves to look omg super hot awesome whatever, everyone will make fun of them when the photo doesn't match.

Some artists do use photos every now and then too. But I assume they don't want to get recognised on the street so it doesn't happen much.