Yes it's a userland workaround and not a fix for the language, but it's thinking about these issues and a PHP extension (offering better performance) is being talked about.
The no-brainers to me are the missing array_some()/array_any() array_every()/array_all() and an array_search() that takes a predicate and iterable. I do these now in userland but an optimized native version would be nice.
What does that lib do that PHP doesn't?