Re: Funk studies
I recommend both Latham's 'Advanced Funk Studies' and Garibaldi's 'Future Sounds'. Garibaldi's book isn't just play alongs. There are some really good funky permutation exercises and applied kit ideas as well as a good insight into linear playing. I would probably say the stuff in it is more technically challenging but there are also some demanding pieces at the back of the Latham book. I think the Latham 'Concepts' is more from a technical stand point but it's still worth a look.