“You guys” makes sense. Sometimes in English it’s better to say “you guys” to clarify that we’re talking to the whole group. Sometime we even say “all of you”, as in “do all of you want to come to the restaurant with us”.  

Good thinking!

The problem is that the accepted second person subject pronoun ( singular or plural / formal or informal ) in English is 'You'

Vosotros could be 'you all / you guys / you lot / you gang'  or whatever is used in the latest fashionable US Sitcom.

But then what about 'Ustedes' ?   Your excellencies?  

The English Language is very much like the definition of a camel... a horse designed by a commitee. 

Spanish is much more precise and the HINTS are there to provide a context that cannot be understood from a short phrase.

So I vote for leaving things as they are.

Not all Spanish learners are English-speaking Americans. "Y'all", "you guys", etc. are regional or informal register and not normally used in standard situations in the UK, for instance. In English, "you" + verb is a one-size-fits-all combination: singular/plural, formal/informal. Where its meaning is not clear from context, we have other means of expressing what we mean. "Are you all coming?", "Are you lot coming?", for example, are two ways of saying the same thing, one more formal (you all), the other less so (you lot). The "vosotros" hint is perfectly adequate for telling all learners what they need to produce in Spanish.