The "improved encounter design" in 7.0 (7.2 onwards?) can be really well made, but it's still their formula of success with a few unique additions here and there. With that in mind, I do wonder what they even consider big enough to warrant the job changes be one of 8.0's selling points, even before the expansion is announced. Do they consider the fight design changes in 7.0+ a big thing?
If we take the current paradigm, I can't see a way for most jobs to grow (and would dare somebody point how) without being massively reworked. Otherwise we'd see just more follow-up actions or new actions enabled by a 120s button press, like how Presence of Mind enables the usage of Glare IV.
I guess it will either be a very meaningless rework, or a massive one to the point that I ask myself how they'll deliver that AND new jobs.