I have a feeling a can of worms may open here...
But personal feelings....
Personally, I don't see the point in using a running rig with leadcore....or with an inline lead. It just doesn't move resistance free like a running rig is supposed to. It kind if just leaves you with a 'sort of running rig' with no real benefit.
Not to mention if you get the smallest kink in the 'core, or bit of lead poke out, you hae yourself a death rig.
Same goes with using a lead clip without the clip firmly fixed to an end swivel, the lead will never eject if the clip is not fixed, and if the lead can't eject, why are you using the clip in the first place?
I like your idea of having a rig that can quickly be changed to a different style, but you have massively lost all the posative mechanics of all the rigs involved in return for a minor convenience.
TLDR: If you want a running rig, use a running rig, if you want a semi-fixed rig, use a semi fixed rig.