That's the problem with melees in general, their additional job unique tools make them unique, but their base combo patterns are all similar, and while it's not on the level of healers with their gcd heals, it's not that far off. I'm also all for more proc based jobs in general. Combos are unappealing, especially with so little or no branches those days. Could just replace them with a single pvp button to reduce bloat and add new fun toys, and we would be better already.
Casters are very diverse yes, and that's good. SMN however, has suffered from the sqenix axe of butchering that MCH went through the past expansion because apparently it's easier to redesign from scratch than fix what's broken, especially when redesigning from scratch is intended to stay at a level so basic that it's literally braindead (SMN) or bland (MCH). Rphys are different from each other, yes and no, because BRD and DNC are actually very similar jobs when it comes to how their bursts play out. Fortunately, their job mechanics are different enough to keep them apart (mostly due to the very unique bard song system). MCH is a travesty and I don't even want to get into how bad and nonsensical that design is.
On mitigation, I'll admit that the recent buffs were truly needed for rphys and I actually appreciate this. However, unlike in the past, everybody and their mothers have mitigation to bring to the party (even melees and casters with addle-feint, and addle-feint is good on a short cd). Tanks and healers now all have a crapload of party wide mitigation tools as well, and RDM even has magick barrier. It's stopped for two expansions to be the relatively exclusive realm of rphys to bring that kind of party support, and while I think it's a good thing that everybody has to chime in when it comes to mitigation, it also removed one of the fundamental aspects that made rphys unique.