I've been playing the Bb clarinet for a long time. A few ago, I bought a bass clarinet. Just one question: how do you balance the bass clarinet (other than the thumb rest) when playing the throat tones?
I just don't remember that being a problem if you have a floor peg and strap. But then I typically don't have to stay on those notes very long. You could always slide your left thumb below the register key for more support?
You can also get the thumb rest moved to a more comfortable position, get a larger thumb rest, or have a second "hole" for strap hook added. I don't like the "move" idea because it leaves the screw holes there. Well, I suppose a sufficiently motivated repair tech could fix that. It's also possible to have some modification to the neck.
I switched between peg and strap for a long while and never became completely happy with either.