This is a wise feature request. I would urge you to file it on http://issues.ez.no
Alternatively, you may wish to modify a copy of the user module within a custom module extension to offer the the customized user/register.php to users (with your additional php code to provide for extended password validation and increased user password security).
That request is already 4 years old! I've just done another unsuccessful search on this site for such a feature / extension, does this mean there's not one?
I vaguely remember an extension did this... but I don't remember what it was and it could even be that it was for 3.10 or something, that memory is pretty old.
Well, then, mbpaex doesn't do anything to ensure the password is not too easy... it just expires the passwords at a given interval.
I still don't think this would be that hard to implement. Basically check to see that the password is not the same as the login, or a variation of the the login - i.e. login12 or nigol, then maybe check the hash against a rainbow table of dictionary words (and that should be generated with multiple interchangeable dictionaries for different languages - I would start with a dictionary of the 500 most common passwords). Then maybe also check with a regular expression whether there is at least one of each: punctuation character, number, letter of each case. There is already a length check built-in.
Actually, if anyone wants to pay me to write this, message me.