More hours...more experienced..is the general rule
1) Not all experience is created equal.
2) Not all experience is relevant to a particular operation.
Beyond about 3000-5000hrs, total experience is pretty irrelevant and the the following question is usually 'doing what?' The correct answer to that lies in the needs of that employer.
What is the big problem with company seniority that the anti camp think needs fixing after all this time?
Is it simply that you are prevented from job hopping, or are you genuinely of the opinion 'I bring more talent than an upgraded FO'?
Every company seniority system has its differences, but the one thing they typically always have in common is that they give eligible FOs a shot at command before hiring DECs, hence the angle of my question.