if your lock ring comes loose while riding often, you should redirect your effort from always carrying a tool to fixing the actual problem.

beer opener = lighter or bottle opener on keyring.

I never need those size box wrenches while on the road.

and I would never attach a tool to my frame that a thief could easily utilize to steal my wheels and seatpost/saddle. that's crazy.

I'd just recommend a stubby 15mm wrench and a decent multi-tool.