Having previously owned medium Giant FS’s (26 & 29), I’d say you’re on the right sized frame. Difficult to be 100% with set-up without seeing you on the bike. As general advice, I’d recommend something like a like a 70mm combined with 720 to 750ish wide bar, or 50/55mm stem and 750 to 780 bars – try and get your bars and saddle about the same height.
Then, I’d strongly recommend getting a skills lesson from an instructor who is a regular 29er rider (being an instructor, I would say that though 😀 ) As someone has already mentioned, 29ers definitely benefit from more a more interactive rider, and they really need to be positively leant over to make them corner. It’s always worth getting someone experienced to look at you on your bike, as they can advise you set up, body position, footwork etc etc.