There is really no reason to discuss alternative methods of integration, as the Nic is the only accepted system seniority list at LCC, and will be the only list implemented in a joint contract. However, I would like to point out the fundemental flaw in your scenario.
First, you are still looking at it as though I am being added to the east list. Lets talk about what my position was. Is it merely the seat I was in at the time of the merger, or was it my status and ranking within the West pilot group, and my future potential ("career expectation") with the airline? You are saying, it was my A320 captin seat, which you are willing to make provisions to help me keep, as long as east furloughees can have my position, status and ranking. Your scenario absolutely strips me of any upward mobility for the remainder of my carrer, as I could not hold that same a320 lineholding captain seat for another 10 years, while the former east pilots enjoy their new found windfall rakning within the company puts them on the fast track to career advancement.
Now the east arguement that the Nic does the same in reverse is pure horse manure. Everybody keeps their relative pre-merger position, status and ranking. The east's own specialist said that career advancement on the east would be delayed by as much as two years vs. stand alone. But the problem is, you did not stand alone, and the West was not being added to your stand alone list. Is two years a lot, considering many on the east were closing in faster on retirement? Perhaps, but Nic could not use age as a criteria, as there are age discrimination laws in this country that would have made that pretty unseemly. So, everybody gets to share the newly formed combined advancement equally, with an edge given to the east by Nic giving you guys the top 517. The Nic is fair, perhaps overly simple, and most importantly the result of binding arbitration.
I pick on Theur a lot in this thread. The reason is he gave an interview in a USA Today article when the merger went down. The whole premise of his interview was that now it was his turn to leepfrog forward, as the merger would supply this large group of people who would come in under him. Absolutely out of touch with the term "career expectation".