by that time by not being exposed to larger dog it may have a life long fear of them that said it is also important that the encounters be positive. It is why I recommend puppy kinergartens because in general they are controlled unlike a dog park etc.I thought maybe when the puppy is older it could play with the larger dogs?
IMHO there are not agressive breed there are indiviual aggressive dogs but labeling breeds does a disservice to a dog. There are certainly basset hound and other small dogs that I would avoid with a puppy just as their are individual larger dogs as well you need to make judgements based on the individual dog not the breed.or aggressive breeds.
Secondly how a dog gets on with people has very little to no bearing on how it behaves with dogs and vice versa. Most dog aggressive dog are good with people and most dogs aggressive toward humans are good with other dogs.