The title's explanatory, I'm just gonna tell you the biggest thing I'm stuck on, and you can try to help or whatever :D

So

The main problem with this is

The deaths

The original book had it easy. We didn't even know what half the tributes looked like. In the bloodbath at the Cornucopia, a little less than half of the tributes were killed, but we were just like "oh" because we didn't know any of them. We didn't care about the deaths of some of the Careers, because 1: they were the bad guys, and 2: we didn't really know that much about them. It was okay to have tributes killed off-screen, because once again, we didn't really know them. There were only one or two deaths that we could actually feel upset about.

But this book... it's a fanfic, and there are no OC's in the Games. Each and every tribute is a character that the readers know and love. So, what I'm trying to get at is... I feel like it would be cheap and disappointing to kill a bunch of the Vocaloids in the bloodbath, even if I only do the lesser-known ones. 

Of course, you could answer this question with, "But Roseh! The Vocaloids are all best friends! They'd never want to kill each other, at least not at the start!" 

Though that may be true for most of the Vocaloids, there are some characters, like SeeU, who don't know the others (See how it all comes down to whether you know the tributes or not?) and don't really care if they have to kill strangers. It's even mentioned at the end of Chapter 4, which is in SeeU's point of view: 

Since she didn't know any of the other Vocaloids (aside from Uni), all she had to do was keep it that way in the arena. This would protect her not only from grief, but also from potential betrayal.

Which brings us back to my original point. We didn't know the tributes of Suzanne Collins' book, so we were protected from grief and potential feels betrayal, and didn't really care who died and how (unless they were one of the five important characters). But once again, we know the Vocaloids, and I don't want to betray you by killing off a character you might like in a "cheap" way, or a kill a bunch at once like at the bloodbath.

So... if you have any advice, feel free to comment or PM or whatever.

(Woah this was a long chapter o.o

Maybe I should also make an update book for stuff like this... what do you think?)