I dont see an issue with seniors on JV if there not good enough to play V. some kids just want to play, nobody wants to go to practice every day, and then dress and not play. i think they should put the kids where they are going to get the most playing time. thats how they improve.
Of course its all about the development of the future V. team, But its still just as competative as V. I dont think that a state tourny for JV would be a bad thing.