The slingshot series looks about the size I want. Not too wide and just big enough for my minimum gear.
Though, does it stay secure while hiking/biking? Or does it slide around when you don't want it to?
If you want to try the 200, I bought a used one for a song off POTN. You can have it for $35. It's in perfect condition.
The Slingshot will stay secure. There's a second strap that locks to the sling from under your right arm. The issue is weight (as it always is). That's why I love the 100. For the weight it can hold the carry system is perfect.