What makes good BE art?

[Snowglare]

Visible growth is key. This is easiest to show in a sequence. In fact, I'd tentatively say it's essential to have more than one image, whether it's comic-style panels or multiple pages. TF is pretty easy to communicate in one image, but single shot BE tends to just look like big breast artwork.

Action lines help, and I agree that facial expression is important. It's generally best to go text-free, as poor writing detracts, and you would want to show emotion regardless. Plus, it's hard to go wrong with a BE reaction. So long as it's drawn well, shock, happiness, pre-faint eyerolling, ecstasy, a taunting you-can't-have-them raspberry, whatever.

Bulging is great, as is clothes-ripping. The two combined can yield a sequence-quality single shot image. Some sort of story can help, again preferably told in pictures; it needn't be complicated anyways.

It's fun to see familiar characters, but only sometimes, and using ciphers carries a lower risk of alienating part of the audience. For instance, I love to see April O'Neil transformations, but have no interest in Pokemon characters changing in any way. And if the character is hopelessly obscure, I'd often prefer it to be no one. Better that than someone I could know but don't.

Also, this is just me, but more realistic art, not all that cutesy stuff. The less anime, the better.

I wholeheartedly agree. Even in breast expansion art, the woman's face is more important to me than any other part of the drawing. If it's too cartoonish, too simplistic, too ugly, it can kill the picture for me.