Hello Vicky, and welcome to COL.
I am sure you will get lots of different answers to this question, but I am a big fan of rescue dogs (I adopted Winnie, a 1-eyed 8-year old last year). Looking at your lifestyle, the advantage with a rescue dog is that it could join you on your active weekend walking from day 1, whereas a puppy's development will be damaged if you over-exercise them.
The difficulty may be your cat, which will be very jealous of a new arrival, but might respond better to a 'baby'.
Some people think puppies are better because you have a different bond with them and they don't come with 'baggage', however you can never be 100% sure how they will turn out whereas with a rescue dog 'what you see is what you get' and a good rescue centre will be able to advise you on the dog's personality. Saying that, you can get a pretty good idea about how a puppy will turn out by meeting it's parents.
Some rescue dogs are already housetrained and can obey basic commands, others not. If you take a look at the 'rescue cockers' section you will get an idea of the sort of dogs that come up for adoption.
Adopting a rescue dog is very rewarding. They are on best behaviour for a week or two and then their personality starts to shine out, their confidence grows, and they relax at home and become devoted companions.
If you decide to go down the puppy route, then the most important thing is to get one from a good breeder and know what questions to ask etc. There are lots of experienced people here who can advise you.
Good luck, whatever you decide.