Feeding for the best development? Personally we do complete prey model raw, and I feel that is most species appropriate. But, I know it's not for everyone. So I won't preach about it.
In terms of kibble, I would not feed Taste of the Wild to a puppy, even though it is labeled as 'all life stages'.. the calcium to phosphorus levels are way too high for a developing puppy, especially one of large breed. In general for a large breed puppy you would want to keep Cals/Phos levels under 1.5% maximum; I have never fed Royal Canin so I don't have comments on that but the only grain free food I would feed as appropriate to puppies would be any line of Orijen excluding their new Red Meat line and their sister grain free line, Acana as their cals/phos levels are appropriate.
It is a myth that a puppy kibble is not appropriate for large breed puppies. Recent studies (I can cite them for you later, if you want) indicate that large and giant breed puppies should be kept on APPROPRIATE puppy kibble for up to 2 years. Sadly, most kibble, even though specifically marketed as puppy or all life stage are not always so - you have to read the guaranteed analysis yourself.
If you are feeding raw recreationally, keep in mind that exposed bone should never be fed to a dog. If you want to feed raw bones, the rule of thumb is that they must be meaty - ie., slathered in meat. This will help to cushion it as they chomp on it, and also in their stomachs. This is perhaps the single largest mistake people make when feeding bones and/or raw, and it contributes a lot to incidences of punctured stomachs, painful bowel movements and broken teeth.
In raw feeding we call these "raw meaty bones" or RMBs; Appropriate RMBs vary from dog to dog depending on jaw strength and size.
Little dogs can have drumstick, turkey or chicken necks, and chicken wings as appropriately sized RMBs, while larger dogs can have something like a pork hocks.
As for supplementation - I would supplement with a good Pacific Salmon oil. For any dog, really. Processed dog food and conventional grain fed meats don't contain nearly as much good fatty acids as they should.. a good Salmon supplement can make up for that.