
I've not had much to do with welsh springers, but they are usually put forward as an alternative to English springers as they are not as nuts which I would agree with.
I reckon the breeder you spoke to is right in what she has been telling you with welshies versus goldens. The calmest will be the show type golden although I might add here they they won't necessarily be the sharpest card in the pack. A dual purpose golden depending on the lines in the pedigree, should be a happy medium and the working bred will vary from hot to very hot.
Goldens love their people and like to be near them when they are about. Mine have always followed me about the house and flopped down nearby to keep an eye on what I'm up to, the only one that has been more aloof and tended not to follow me was the show bred golden. However I've never had any problems with separation anxiety, apart from when they are in their first few weeks at home with you when just moving away seems to be a major emergency. Once past that stage my goldens have always just waited patiently for me to return and at the ready to greet you with a soft toy (or a pair of socks).
They are happy with a moderate amount of exercise, an hour mainly offlead is fine generally, but if more is offered then they will be there waiting for the off.
Goldens are still pretty sensitive, shouting is out unless they happen to be much further away from you. They are quite capable of looking like an rspca advert just because you've raised your voice.
Hope this helps