A 787 is roughly a replacement of a 767, although it would be likely to be flying more LH routes than the 767 was in it's later years.
You could put the 787 on the 767 contract and no-one would be realistically too upset.
By my back of the envelope calculations, putting a 787 on an A330 pay rate - but without night credits or overtime - would roughly approximate the 767 salary, with the exception that all pilots would be paid about the same instead of the senior creaming the overtime.
You don't need overtime to "persuade" crew to complete the job. Crew will complete the job unless they are too fatigued to do so. No professional pilot would disrupt hundreds of pax unnecessarily.
Overtime has always been the absurd inequity in LH. To be paid so much more for sleeping 8 hours in a bunk has always puzzled those of us who fly 11 hours actually flying 11 hours for less pay. Overtime, if you like, has "killed" the LH contract.
Having equalised the salaries of the crew, rotating seniority could also be a reasonable option. The vast majority of those that have tried it, like it. If you don't think you'll like it, don't bid for it. Should have been done on the A330 - oh, hang on...
The comment above that everybody experiences instability in such a system is rubbish. The reality is that all experience stability most of the time, instead of the few taking it for the team for years on end in stagnant times.
I prefer to work in an environment where everyone "makes the coffee" now and then. The psychological improvements are staggering. It's a much nicer environment. Puts a smile on your face.