I will be adopting two small dogs. Does anyone have any idea on a good combo...?

Unless you are experienced with keeping dogs, and particularly multiple dogs, can I urge you to take just one at first. If all goes well, in another year, then think about adopting a second dog. I'm rather surprised to be honest, that the Humane Society haven't warned you about taking on two dogs, puppies or not, at the same time, unless they have always lived together. It's far far easier to concentrate on gettng one sorted out, rather than two.

A male and a female, provided they are neutered of course, is usually the preferable combination, although it is possible to have two of the same gender. We had two males, one coming in 10 months after the first incidentally, and apart from the occasional spat, both lived together just fine. BUT they were Bassets, who are not known for beingworried about being with another male. I'd avoid two terrier males - IF you go ahead with two. But again, please think very hard about this before you take on more than you can handle.

ps You will be looking at training out unwanted behaviour, which most rescue dogs will come with, unless you are very lucky. There is usually a good reason why a dog ends up in Rescue. Sometimes not always immediately obvious.

You need to do more research. If you have your heart set on a pittie then get that dog first and realize that you will probably only be able to have that one dog. If breed is not that important to you then try to find a pair of dogs that is already bonded. I can't tell you how often I see shelters and rescues trying to adopt out dogs that are bonded and have to go together. All other factors aside, it usually works best to have one of each gender. FWIW, knowing both breeds, I doubt I would ever have a Shar-Pei and a Pit Bull together. They are both dominant breeds famous for dog to dog aggression. Hopefully any shelter or rescue you are going through would know better.

If you are adopting them both make sure that they are ok with each other first. Whether it be male or female they may not even like each other. Dogs have different personalities just like humans, there are people you like and do not like. Are the dogs your looking at share the same kennel? Do they interact? Find that out first and then decide.