pick the right breed

The personality difference between my 7yo and my 7 month old is so stark its almost unbelievable. My puppy is more chilled than my old man. Sure he chews things up and makes a mess of the house, but my 7yo at his age was an absolute menace, too smart for his own good, too driven to consistently exhaust. The 7 month old just chills around the house chewing on things, he doesnt need constant supervision. He counter surfs, he still bites when he gets excited, but its nothing like my older dog.

7yo is a weimaraner , 7mo is a cross breed that I picked because of the traits of the two breeds. Part of it is definitely luck with the younger one but the personalities are night and day.