Two of the mesivtas mentioned above are actually part of the Chofetz Chaim system – PTI and Texas Torah Inst.
A pretty good “comprise” HS where you don’t have to sacrifice Chol for Kodesh or visa versa is Ateres Yaakov (South Shore) in Lawrence. Many boys went to college after a year or so in Israel, some are now in the Mir.
But I still suggest you look into Chofetz Chaim.