When I design my campaigns, I usually have set roles that I need filled.
EX. My current campaign had five roles, the Abonimation, the Noble, the Wanderer, the Seer, and the Worshipper. In this case the worshipper is a Dwarven wizard, and the roleplaying fun we have as he debates the merits of arcane magic versus divine magic with the party noble creates some great stories.
I love listening to my players figure out how to fit their character archetypes into the roles I have established. It gets them interested and allows them to figure out how they fit into the story. Making my job a lot easier.
That is something I would never do. I restrict races that I feel will be disruptive to the game, but I would never tell the players what kind of character to play beyond a few loose guidelines such as: Can't be evil, can't be the same class as another character (with possible exceptions)
You don't need a specific ract to be a specific archetype, but its so much more fun rather than being the human I am every day when I wake up. That is the point of roleplaying in the first place. Becoming something you aren't and developing a collaberative story from there. That is what makes it fun, and that is what draws people to our beloved hobby.
Most of literature and film would like to have a word with you.
I see a lot of posts saying: You can be whatever race you want, but there will be consequences.
So you are giving permission to the crunch but not to the concept. I think that is the wrong way to go about it. In the end there are restrictions on what kind of personality your character can have due to the nature of the game.
Our group is strictly cooperative for example. Your character must want to adventure with others and help each other. By extension your character must also care about the plot that the other characters are involved in. Character arcs must also fit into the framework of things that are involving to the other characters.
It simply won't do to play evil devil-man who is on a personal conflict of good and evil when none of the other characters care and it has nothing to do with the plot.
When you have a character backstory specific spotlight in game it should brighten the group. The group should care because it involves them. It shouldn't just be your personal story that the rest of the players just listen to.
"But that's what my character would do" is not an excuse. Don't make your character that way.
It is my job as DM to identify character concepts like this and stop them before the game begins. So I won't tell you what you need to be, but I will certainly tell you what you can't be for the fun of all involved.