Honestly, other than the fact that she was played by Majel Barrett, I really don't think that was anything that extraordinary about the character. At least nothing that makes her any more worthy of an appearance than any of the other recurring characters that haven't appeared yet, like Lesley or Kyle.
I agree that Chapel was not 'extraordinary' as a character (Helen Noel made much more of an impact in her one appearance) but that does not also mean that she could not make a meaningful contribution to a story. She certainly had more personality than Lesley & Kyle plus she was a woman - and there is a very visible shortage of women in the franchise at the moment.
Janice Rand on the other hand had bags of personality and is easily updateable and easily includable even if only in a minor capacity. She was more memorable than Kyle, Desalle, and Lesley but she didn't make the cut either.
Carol Wallace has a specific significance to the plot that the generic supporting crew will not generally have. Other characters may only be needed for a role that is relevant to their skill set or to showcase their personalities. Chapel stumbles because her skills set is eclipsed by McCoy while she is chained to sick bay. For this reason, I hope it is their intention to do something with her in the comics and I hope that a 'modern' Chapel will not be so passive in terims of her story contribution when she finds Korby this time round!