level requirement for bh!

ok so.. noobs call everyone to bh but 1 problem... there lvl 90 and were 120+ noone can attack them so...i think only if low lvls could attack the high levels but high levels can attack them only if low level attacks them first. this is my solution to the problem. or make low lvl crater, med, and high. that a way we could just say... high levels to high lvl crator etc..