Set your Bitcoin address in your profile is useless. Because if your account is compromised, hacker will be able to change it. Take it off or change it.
It only makes sense if you sign a Bitcoin message from an address you control the privaye key, and stake it in the forum. Then it must be quoted by other members. Then if your account is compromised, hacker will only be able to delete your post but it is not enough. Because there are quoted posts by other members.
If you can sign another message from that address, you can prove ownership of your account.
You forget about archives. The OP's account isn't old enough for us to say the archives can be deleted as well.
https://bitcointalk.org/index.php?action=profile;u=3493225But besides this, you can understand the OP, because of his loss of a fairly large amount, and make a privilege to access his account. Especially since the OP assures that he has evidence in the form of mail.