Very good discription mate, the whippet is a breed that I will go back to in the future, sometimes you wish you had a bigger dog on the end of the lead but you can't help but love there attitude to work if you get the right one
I had a Lord of the knight bitch, only small but got stuck in to all sorts. Had a big heart and amazing temperament, if you could have put her at 24" she would have been some bitch.
Have you thought about a cross bred mate? Maybe terrier cross spaniel. Straight terriers can be a pain in the arse if you got a lot of big fox or badger places on your permission. You and your son may have a few headaches on your hands
There's unbelievable amounts of chavs around South Wales and I'm sure it's the same the whole UK breeding all sorts of frenchies and bully things for top money, majority don't have a clue about how to care for a dog properly. A lot of criminals do it because it's easy safe cash. Some type of license would be a good thing in theory but can't see it being policed and the people who want to get around it will somehow