Is there only ever 1 send address for a wallet I know you can create label / address pairs to receive coins and also that a wallet automatically generates a new address when you need change from a transaction for the receive operation.

Will there only ever be one send address for any given wallet?

So on the blockchain all my send transactions will only ever have the one address even though I can and will have multiple receive addresses?
It doesn't work that way.

Any address can send and receive. Since you'll receive coins on multiple addresses, sooner or later you will have to use those addresses to send too, in order to spend those coins.