You think you'd be over that prank at your age.

[wanabee]

Dear all,

Will you stop that prank already? It's no funny. You're twenty-four, and
1 you'd be over that kind of stupid prank at your age.
2 normally you'd be over that kind of stupid prank at your age.
2 you think you'd be over that kind of stupid prank at your age.
3 people think you'd be over that kind of stupid prank at your age.

I made them up. Do they all work in the context? And if any one of them is unnatural English, please point it out.

 

[wanabee]

Thank you very much, perpend!

 

[Edinburgher]

I tend to read "you'd" as "you would", no matter what. For me, therefore, (1) does not work unless you change "you would" to "you should".
(2a) is fine.
(2b) doesn't work. It needs to be "you'd think you'd be...".
By the same token, (3) also needs "would" after "people".

 

[Myridon]

I agree with Edinburgher. Only the first number 2 is okay.

 

[wanabee]

Thank you very much, Edingburgher and Myridon!