Correct me if I'm wrong, as it wouldn't be unprecedented and my familiarity with other languages is limited, but to the best of my knowledge English is the only language without an acceptable plural to indicate the collective 'you'.
We need one.
This need is met regionally, with each dialect developing it's own answer.
I'm partial to 'ya'll'.
Ya'll makes sense to me. You all. All of you. It works, it sounds kind of nice to my ears, it fills that need.
I understand now, though, in some southern sub-dialects that 'ya'll' is used to indicate the singular and 'all ya'll' is used to indicate the plural. Well, that makes a little less sense... It does, however, make me feel a little better about that time I spent in Texas. When people would call just me ya'll, I would go home and whine to my roommate, "I know I'm BIG, but I don't think I'm PLURAL!"
Where I grew up, the generally accepted term is 'youns'. I'm sure at least one of my Western PA friends will debate me on my choice of spelling. Spell check isn't so sure about it, either. I have seen it written out as 'yinz' and 'yunz'. Youns makes the most sense to me, as it is at least an attempt at a contraction. (you ones?)
Youse? You guys? Youse guys? Youns (yinz, yunz) guys? All regionally acceptable terms in the vernacular.
Yesterday, though, I heard a new one. My family went to the movies, and, as the usher tore our tickets he said, "Enjoy your guyses show."
We need to come to some sort of agreement on this, because that? Was just out of hand.
Ya'll have a nice day, now.