looks like you got a pretty good start to a collection. The Avi .40 is a great trainer if you dont know how to fly yet. Depending on the servos, I wouldn't replace them. I've using hundreds of Futaba and Airtronics servos with not failures... though they may have a little slop and low power, they are damn near bulletproof in the right circumstances.
I dont know cars or helis though so i can't give you any feedback there.
The 2 channel TX may be one of the cars you got, but without the pictures I couldn't tell you.
The flight box sound like an impressive parts and tool collection.