I think at first, Harry won't be involved in the newsletter until he's been forced to participate during the Triwizard Tournament. I think Luna was given the task to write the newsletter due to her father whose job is writing and publishing The Quibbler, and even though she is a Third Year. This also will get her into the Yule Ball without a date, since she'll be reporting on all aspects of the tournament and the events. She is a year behind everyone else after all, and so like Ginny, she needed a date to get in, so this way, she's still able to get in without us breaking character and having someone asking her.

And just now, I am realising just how much resentment there is or could be. 1st Year? Harry defeats Quirrell / Voldemort, and Ron's achievement is just really skipped over. Sure, he risked his life to get Harry further, but when it came to giving out the points? Hermione got points for being intelligent, Harry got points for bravery and even Neville got a very points for having the courage to stand up for friends. But Ron? He got points for being good at Wizard Chess. Nothing about him risking his life. In Chamber of Secrets, his sister and everyone else always thanked Harry for saving them from the petrification and Tom Riddle, but not so much her brother. And of course, as you've so mentioned, there was Hermione and Harry pretty much running off and saving Buckbeak and Sirius by themselves, and then throughout the Triwizard Tournament, it will be mostly Hermione helping Harry learn spells for the Trials.

There is just so much leading up to him feeling left out that I feel almost a little silly for not noticing sooner.

Well for the starter, We could say Luna is about ready to leave the Great Hall when Draco does his show off thing and goes to put his name in the goblet, but Snape will intervene and grab him by the arm. Of course, he's dragged out the Hall and is being lectured, so whilst Snape is deciding on his punishment he spots Luna Lovegood leaving too. Severus remembers that she's the Ravenclaw who is in charge of writing the Newsletter and so he forces Draco to join her in writing the newsletter. Meanwhile, Hermione is waiting in the library, waiting for Luna to arrive, and I guess we can say that Harry is there with her, half out of intrigue about the Tournament since he doesn't know as much about the Wizarding World as others, and the other half is to do his homework, of which he has to be reminded to focus on by Hermione.