Probably half the Goldens I know are reactive. D: To dogs of course. Very soft with people, but DA/DR seems to be rampant in the breed nowadays. They tend to be very stubborn, too, my least favorite breed to groom by far.
Standards are nice dogs, but I can't see you with one! They are a bit dorky and serious. The grooming is painful!!! This is coming from a groomer. It takes 3 hours just to bathe and fully blowdry a Poodle, much less clip them. Unless you get your Poodle completely clipped down (which I think makes them look fugly), you're going to be spending hours brushing that coat out, detangling, and around $500 a year on grooming costs. PRA, vWD & allergies are very common, affecting most of the Standards I know, including all 3 of my boss's dogs. They are lovely dogs but without allergies or a special affinity for the breed, I wouldn't recommend it.
I think a Smooth or Rough Collie would work very well with all of your needs! I've never met ONE who wasn't just a dream... they are happy to a fault, and very smart but not demanding like a Border Collie. All of the Collies I know are great with all dogs & people, they really have hearts of gold.
I wanted a GSD, but now that I'm having a baby, I'm leaning more towards a Collie for my next dog. Idk if I want to deal with training and working a powerful, intense breed and a toddler at the same time.