6 weeks! He certainly is a big guy! Does the breeder have an idea of his adult size? Sorry for the length of my posts I just feel like there's so much great info to share!
1. I try not to use hot dogs as training treats because of the nitrates and fillers and parts-is-parts. Plus I just don't care for the texture in my hands. Very slimy. I usually turkey bacon from Trader Joe's which my pup does pretty much anything for. It's cheap and healthy. It's great for "leave it" , recall and "find it" games (because it's pungent).
2. For an intro to raw feeding, check out this video: Raw Meat Diet for Dogs and Cats - YouTube
Then this article:Common Raw Feeding Mistakes That Can Be Harmful to Your Pet
I think it might answer a lot of questions your GF has. Have to say that raw feeding will NOT negatively affect your dog's temperament. You can only get GREAT results from a proper, balanced raw diet. That's like saying eating YOU ketogenic (predominately protein-based) diet would make YOU bloodthirsty.
Thankfully there are companies who have taken most of the guesswork out of raw feeding, especially at the intro stage. Check out Bravo!..the pre-ground format is really attractive to puppies as they don't have to do a whole lot of chewing. Supplements like coconut oil and plain kefir are a good idea. You can supplement with a raw knuckle or femur for after-mealtime teeth cleaning. As a pre-dent student you should definitely be able to appreciate the pros of pearly whites and the absence of gum disease later on!
I switched my pup to raw right after I noticed her coat was beginning to look dull and her hyperactivity was off the charts. Also she was developing skin allergies.
3. As for the potty training it only took me a couple of days to reinforce the idea that jingles=potty. Just be consistent and hit that darn bell every time you go outside. Make sure Mushu knows what you're doing. Hold a treat by the bell, get him to touch it with his paws or nose, then say "business!" and open the door. Yes, every 30 mins should be fine. If you're playing outside the crate or confined area, you might want to slash that to twenty.
4. Also..you might want to start by feeding him in the crate. The crate must be the place where only good things happen...food, treats, chews, toys...you get the idea. I heard that wrapping a ticking clock (imitating his litter mates' heartbeats) in a towel and placing it in the crate for the initial housebreaking can make the pup feel more secure. I personally didn't get around to trying that one...but it might be an interesting experiment.
5. As for recall in the open field...you better add a 20' nylon leash to your list. This will allow you to work on recall in a space with a lot of distractions (smells, sights, etc) while having complete control of your pup. Training Positive on YouTube has a great series of introductory training videos. Do you have a clicker or are you going to use vocal commands only?
6. Just have reasonable expectations...at this point with the puppy it's all about playtime and fun and learning the rules of the house. Puppy obedience classes are a worthwhile investment. Look into puppy agility for when he's a little older. I got this idea after watching my pup create her own agility course with the household furniture.
Don't feel pressured to socialize outside of a structured setting such as puppy class. I'm glad I skipped the dog parks. Your little guy is going to want you to keep him safe from bigger, older dogs. Until he his closer to his adult size and mental state, he doesn't need the trauma of getting picked on at the dog park. That being said, he will need guidance from older well-behaved dogs. You might try to get him around stable GSDs with good temperaments. Maybe your breeder or trainer has suggestions?
7. Funny story--I was out at the park on Saturday with Herzen (my pup) and I was approached by a MWD handler whose specialty training is bomb dogs. I don't know why but she goes crazy right now for law enforcement guys and military...she just wriggles her tail off when she see policemen! I think she's trying to go K9 on me.
Luckily with these individuals the love is mutual.
Anyway, the MWD guy told me that they don't even start working with GSDs until two years old. This is not the first time I've heard this. True enough, Herzen is a highly-intelligent goofball right now at 8 months. The MWD handler said she appeared to have every indication of a great sniffer. We're already working on upping her SAR game.
Keep researching the interwebs, you sound like you're doing a great job! If you think of anything else to ask just let me know.