Hur strukturerar jag upp denna databas på bäst sätt?

CREATE TABLE users (
         id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
         name VARCHAR(100)
);
CREATE TABLE attributes (
         id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
         name VARCHAR(100)
);
create table userattributes (
 userid int not null,
 attributeid int not null,
 FOREIGN KEY (userid) References users(id),
 FOREIGN KEY (attributeid) References attributes(id)
);

insert into users (name) values("hans");
insert into attributes (name) values("hair");

insert into userattributes(userid, attributeid) values ( (select id from users where name='hans'), (select id from attributes where name='hair'));

- Vilka users har "hair" attributet ?
select userid from userattributes where attributeid=(select id form attributes where name='hair');

-- Vilka username gav frågan ovan..(OBS user.name är INTE IDENTITETEN, det är userid)
select users.name from userattributes join users on users.id=userattributes.userid where attributeid=(select id from attributes where name='hair');