Ah, the wonderful character development! This episode added a ton of new things to the characters, especially Sayaka and Kyouko. Kyouko revealed her past and became a completely different character from who she was at her introduction. She’s still the experienced Mahou Shoujo, but the way she became a mahou shoujo is a really tragic one (which looked awesome, by the way). Sayaka meanwhile takes an entire episode to let the revelation of the previous episode sink in, to the point where she believes that she can’t even have a proper romance anymore.
Do mahou shoujos aged? From Kyouko's flashbacks, her sister and her mom are wearing old style clothing, but she is the only one that is still wearing modern clothes, also notice the buildings and the old style street lamps.
I don't see a good end for Sayaka. Don't know whether mahou shoujos will become a witch (the witch in episode 1 looked like Sayaka) .