Bad idea... there are specifics that define animal techniques, theories & applications. Changing a punch to a claw hand shape does not make it a "Tiger". It makes it more likely somebody's about to break a finger or more.
You're right, replacing a closed fist punch with a tiger claw would probably be disaterous unless the palm heel is used. Could be worthwile in a situation where you don't want to hurt you'r opponent.
British12 has a good point, I'm confident that the techniques in the forms would make themselves quite useful. A snake strike into the throat is a very powerful technique, as can be crane snap kicks and leapoard strikes.