(All of the below is my opinion from having a go on mates bikes, we all end up with a similar setup and.. of course, assuming you have the right size frame)
720ish bars... that bit is easy. Any bigger and they clatter into things, they don't fit in the car and the steering is weird, resulting in you falling down a lot.
The stem is more difficult, but I've run a 70mm - 0 Deg for ages on multiple bikes and it feels fine. Shorter and I feel too compact on the bike, longer and it handles like a barge.
Rise is related to your bar rise too (but I always use low rise anyway) as a rule of thumb, if you feel like you're going to fall over the front on that slow steep stuff stick a 5deg rise stem on. Another way to do this is have a travel adjust fork that can chuck the front end up.
In fact, forget all that, you're just going to have to try a few and feels what's right for you and the bike together. I bet it'll end up being 720 bars and 50-70 stem.