Survival hunters have 3% tooltip crit from talents, feral druids have 11%. Also, at level 70, druids only need 25 agility for 1% crit, hunters need 40.
As for there being a crit "cap", if you're hit-capped with 0 expertise and attacking from the front, you're actual crit % will cap at around 50%. Any extra crit % will be pushed off the table by glancing blows, block, parry, and dodge. When you're attacking from behind, the crit cap should be around 66%, since you only have to deal with glancing blows and dodge.