I would like to be
I want to be
What is the difference between them?
I think 'want to be' sounds stronger than 'like to be,' but I'm not sure if this is true.
They are almost the same usually. Most of the time, "would like to" sounds more calm and fancy to me. For example
I want to be a surgeon
sounds more assertive than
I would like to be a surgeon
So I guess your assumption was fairly on point.
One situation where I see them as crucially different is when asking for something to be done to you, or for you. When using "want to be" it sounds more like a demand and less like a request. If I were the boss of a group working on a project, I could say something bossy, like:
I want to be updated at every step.
Whereas if I am equivalent to the other team members, I would request as such, more politely (I guess a boss can be polite too, though):
I would like to be updated at every step, please.
Below is my previous answer, which was about the wrong thing—I didn't notice the 'be' (sorry) but I think may be useful for some, so I'll leave it.
However, I feel that none of those answers contribute good examples of which context you would use each in. I think this is what makes them the most different—the fact that "would like" sounds more polite in certain contexts, in many of which "want" isn't quite appropriate.
If I'm talking to someone I know, I think the following are equivalent
I want a backrub = I would like a backrub.
In a situation where you're asking for a service or product from a stranger, I would not use "want"
I would like a cheeseburger, please.
I would like more information about this service.
These would sound strange and rude with "want."
Generally, "want" sounds much more assertive too. You could use it when demanding something, instead of asking for it, for example
I want justice!
I want eBay to stop charging me random fees they can't explain.
In grammar 'would' is used in the 2nd conditional for present or future unreal or imaginary circumstances. Eg. If I were you I would quit my job. If I had a million dollars I would buy a house. I cannot be you and at the moment I don't have a million dollars; they are not real.
It is also used in the 3rd conditional for past situations. Eg. If I had worked harder I would have made more money. If I had won the lottery I would have gone to the moon. The situation could have happened or it could be completely impossible.
In every day life we use it in polite requests. I think of it as... we give the requested person the option, or condition, of denying our request. Want is a stronger demand that does not imply the option of a condition. Eg. I would like you to come to with me. I want a cup of coffee.
I think of it like this: we have wants for ourselves (I want earn more, I want to go to bed, I want x y or z - anything really). But when we project these wants to other people in the outside world we soften them to 'I would like', or 'would YOU like'... We can say to someone else(like above) 'I want a cup of coffee - shall we go for one? Or: 'I want a cup of coffee, do you want one?' But we would say this whilst at the counter waiting to be served - discussing with each other what we are getting - like in a direct 'yes' 'no' scenario. But going back, its more polite to say: would you like to come for a cup of coffee? I want one myself.' Or better still: would you like a coffee, I would really like one' here we are discussing the future and it keeps it a bit open - rather than dumping our demands (wants) onto it - it's kind of selfish and lacks finesse dears.
I would like to be an astronaut. I will never be an astronaut. Too old, not fit enough, so I won't do anything to become an astronaut, but I sure would like to be one.
I want to be the winner of the next town archery competition. I practice two hours every day to become as good as possible.
I'd use "I would like to be" for fanciful wishes that are not going to come true. I'd use "I want to be" for something that is my target, and where I spend effort to make that ambition true.
In practice, the terms are used interchangeably, and people see nuances in implied meaning or tone. The dictionaries include definitions covering common usage, in which these terms are used to describe the other. But fundamentally, "like" refers to enjoyment or pleasure, "want" refers to desire or wish.
In most cases, those are closely related, so either term conveys the same intended meaning and people don't make a distinction. The difference becomes more apparent when those concepts don't correspond in the usual way. For example, a masochist might like something (get pleasure from it), and for that reason would not want it.
I believe it was Sir Rod Stewart that said "If you want you my body", and not "If you would like my body"
Because then you would maybe let him know, instead of just letting him know.
'I want to be' is a bit stronger in tone. Picture yourself swaggering into a Subway and yelling at the sandwich maker (a young high school girl): 'I want a foot-long Veggie Delight...on Italian bread!' It's a bit strong--bordering on rude. Now picture yourself patiently waiting for service at the counter and softly saying 'I would like a foot-long Veggie Delight on Italian bread, please.'