I agree, great idea! I hate the stock locking clutch since in the "locked" position it is barely engaged.
Since I have to get a new brake lever for my drum brake that is coming in next week, I might as well get a pair and do this on the clutch side. Thanks for the great idea!
I think I will reverse the operation on mine, though, and have the locking function be manual and auto-unlock when the lever is pulled. As in, pull the lever, flick the lock to engage. Then pull the lever again to auto-disengage. Maybe I am just an oddball, but the majority of the time I pull in my clutch is in situations where I am not looking to lock it. We have a bunch of stop signs around here, so a whole lot of short term clutch activation...