One thing I like about PBS is, you build your own line (seniority permitting of course). Under our system (and they are all different from what I've heard) we chose the trips we want to fly AND we choose the days we want off. If you are senior, you can hold both, the best trips and the best days off.
Even if you are junior, you can usually get the days off you need for Mom and the kids, the Guard, etc. but you might have to eat some crappy trips to do it. Under our old "Line of Time" bid sheets, the lines were built by crew schedulers, without regard to consistency in days off or trips, they just built lines that fit the mold.
Even if you were the most senior pilot in your category, you might not be able to find a single pre-published line that had both the trips you want, and all the days off you need.
You then had to hope you could swap some trips for the days off you really need, etc.
When our PBS first runs and builds your line, there are still caps, but they could only be as high as about 82 hours. We left some loopholes open as far as swapping a low time 1-2 day trip for a high time 4-6 day trip, after the bids are awarded. That's how guys can be awarded a line with say, 77 hours initially, then they can swap up to the FAR max of 100hrs. in 28 days.
If we had kept that one loophole closed, Delta would have had to start hiring years ago, instead of just last year. There are a few other loopholes too, all of which lead to more flying, less hiring.
BUT...some pilots LOVE it and don't ever want those loopholes closed.