Surely it is blindingly simple, as has been said so often on so many similar Threads ...
1. Call Gold/F/whatever.
2. WAIT until they have come forward.
3. Call Silver/CE .. and WAIT
4. Call Bronze ... and WAIT.
5. Call the rest.
For Heaven's sake, it's so bloody simple. Instead, what do you get? The whole lot gets gabbled out in one sentence, so everyone vaguely entitled surges forward and any sense of priority is immediately lost.
And do some sensible signage, while you're at it ... at Shoulder level, not down at knee level, so that people can see it in the throng. Forget the artistic small fonts ... use BIG LETTERS!
OMG, it's so bloody simple a schoolboy could organise it better.
How long do you think the 'Turn-around' times are !. An A319 turn time is 32mins, which includes Disembark, cleaning, catering, security check and onload. The outstations can just about manage it (LHR consistently gets no where near it), but anything like you suggest will just prolong the 'Turn-around' time.