Seniority list have probably had their day.
At the moment, in the UK, they are open to legal challenge on 2 fronts:
1. The higher up the seniority the generally older you are. Using seniority for pay, benefits etc is open to challenge as against the new age discrimination law.
2. A seniority list does not account for male / female split and therefore is open to challenge on sex discrimination law (this also applies to ethnic background or religion if the company keeps a record of these).
One disgruntled pilot taking private action could bring the whole system down, at least in the UK. This does not apply in the US where specific legislation allows use of seniority lists.
It’s also my belief that seniority lists also insulate pilots from market forces. When pilots are freely available it ensures peoples pay and position are protected. It also prevents companies from lowering their pilot cost during these times. On the other side when pilots are in short supply, like at present, it also prevents pilots increasing their salaries in line with the market, except for very low seniority guys, who are prepared to move to a new list. Companies benifit as pilot cost pressure is not that high.
Again, my belief, but every other profession mentioned are exposed to market forces, except pilots. Take lawyers, too many lawyers in an area, or someone not being as good as the others results in a reduction in salary. Too few or your an excellent lawyer, increase in salary. I don't really see why pilots should be different in this respect.