I like particular elements and aspects from several different works, and I would like to incorporate them into my piece. Would I be considered a 'copycat' or 'unoriginal' if I go through with it? For example, I really like the element of 'color-blindness' from The Giver (Lois Lowry), and something similar to the 'arena/fight to the death' like from the Hunger Games (Suzanne Collins); I would like to incorporate these two elements into my story, but I just don't want to be seen as, "Oh, it's another one of those novels...", or "That part of the story reminds of me ________'s novel. Copycat much?" I mean, obviously, I wouldn't be copying the authors' works. I would put my own twist and my own meaning to the elements. I just want to hear your thoughts about this.
It depends on how it's written. "Arena/fight to the death" could just as easily describe Roman gladiators. If it's done in a new and unique way you won't be accused of copying.
If there isn't anything in the story that's new and interesting, I'd see it as a copycat. If there's lots of new and interesting stuff and just happens to have a few items that overlap with other books? Not as big of a deal.
Pragmatically: I personally would not call you unoriginal for doing what you describe in the OP. The very fact that you ask this question indicates that you care about the quality of your writing. You are thinking of incorporating these elements because they interest you, not because you want to capitalize on the popularity of other books to make a quick buck. Therefore, it is inconceivable that you will fail to offer something interesting to the reader. Just focus on writing the best book you can write. If borrowing elements makes it a better book, then, by all means, borrow them. Just keep in mind that if enough people read it, then no matter what you actually wrote or which elements you borrowed, someone will accuse you of unoriginality. It is impossible to please everyone. Furthermore, accusations of unoriginality tend to be parroted by the masses (oh the irony) because, when casual observers "recognize" parallels between a creative work and an earlier creative work, they can easily be deluded into thinking they are culturally literate and clever, and talking shit about authors makes them feel better about themselves. Philosophically: Quality is achieved through revision. We would be nowhere as a species if we did not observe what had already been done, and then do it better. The first person to do something does not deserve a monopoly on that thing. The public interest is the highest good. The way to promote the public interest is to maximize the quality of the selection of creative works available to the public. The way to do that is for everyone to make the types of contributions they are most equipped to make, whether that by is coming up with new ideas or by refining the expression of ideas that have already been expressed. And when you think about it, the only thing all authors have in common is that they specialize in expressing an idea. The measure of an author is how well he expresses an idea, not where that idea comes from.
You can be certain that anything you include has already been done by someone. In that context you are not going to have anything original. The way in which you portray it is what makes the difference.
I'm not familiar with either of the novels, but based on what you've described, color-blindness is pretty common, and Collins didn't invent arena fights, in fact, I'm thinking Ancient Rome when I think of arenas (and it may have been done even before that) and fights to death, so she's just as much of a copycat as you'd be. As in, not at all. If you lifted something very specific, it might raise questions, but ideas aren't copyrighted, so basically you could just write about a girl with a bow who enters a reality tv fighting contest, I guess.
I think I'd worry if there was another story out there about a color-blind girl fighting to the death in an arena, but if that isn't the case, just go for it. I think general ideas are fine to re-use. Specific ideas probably aren't. Hard to draw the line, but do try!
Even if there was a story like that out there, and @United borrowed those elements and wrote a higher-quality book, then that book would have my praise. (I guess I am biased, since my current project is to write a novel that is higher-quality and more accessible than the fanfic it borrows its premise from.)
I think the problem would not be lack of praise, but potential lawsuits! If you decided to re-write the Harry Potter books because you thought you could do a better job, I don't think you'd get away with it, even if you did do a better job! It's okay to borrow elements from other stories, as long as you don't borrow too many from one particular story.
That's far from original to begin with. And, considering Hunger Games is already 'not another one of those', that reaction is inevitable
I heard someone say (or write) once, that a good story is 1/3 made up, 1/3 based on ones own experiences and 1/3 stolen. I think that sums it up pretty well I think most writers do that, they take something they made up, spice it up with things they've once read or seen and use their own life as a source in some way in order to understand the characters better. (as a sidenote: You can also give the characters traits that represent different sides of yourself, or base them on traits from various people you know in order that no one would recognize themselves. Stealing is a part of the writing life just do it in a way that no one can trace it back to the source.