I don't like a system that doesn't allow me to remove the strap from the bass. Too often we hear horror stories of roadies/guitarists/ singers/ even bassists tripping over a strap when the instrument is on a stand (as in your top photo) and breaking the guitar. I tend to leave the strap off right up until I'm ready to start the gig. Much less danger that way. I also noticed at his London gig last year that Stanley had started using the factory straplocks.
Does your method allow for any rotation of the strap in relation to the bass? I know that my playing position changes from moment to moment so any 'fixed' connection would be bad thing for me. All this is of course personal preference. There are as many methods of fastening a bass to a strap as there are players and we all like to think we know what's right ;-)
Graeme
