Thanks for the great reply! Yep, we've looked into Labrador Retrievers, although because they're pretty cancer prone, we're quite hesitant to get them.

Yep, I understand that a GSD would need quite a lot more work, so if we do decide on a GSD, we would definitely be getting them into some agility work with the local dog club, although this will be the first time that we do something like that. Our golden retrievers are/were pretty uninterested in agility, unfortunately, and much prefer to swim.

I definitely do understand that all breeds have health problems, and I'm not trying to look for a breed with no health problems at all. Honestly, it's pretty much cancer-prone breeds that we're trying to avoid. We had to put our young dog to sleep (about a year ago) because he was suffering really horribly from osteosarcoma, and we lost one of our first goldens to cancer too. I mean, if possible, we would like to avoid going through the pain of losing another young dog to cancer. We do understand that any dog can get cancer, but goldens seem to be particularly prone to it...

I've read some of the posts about reputable breeders, and they're really helpful.

Thanks again for all the advice and info!