Creature Handler Archive

I am 4/3/0/4 CH right now, giving me Taming Wild Creatures +60 and Taming Vicious Creatures +35.

The reason I came and asked about taming vicious creatures is because I tried taming a Perlek Scavenger ( aggressive, grows to CL 47 ) earlier today and wasn't able to. Since the only other increase to the Taming Vicious Creatures mod is from master, does this mean only MCH can tame these relatively low (compared to CL 70) aggressive creatures?

Is the master box really that big of a difference to jump you from CL 35aggressives to CL 70? If so, that means all the aggressive tameables CL 36-65 or so are pretty useless, am I right?