The 2nd Job Trait seems a bit overpowered as it would overshadow buffs from other mages like Haste and rival a WHM's fully-merited Shellra V. I do like Krabnuckle's 1st proposed Job Trait, though. It meshes well with SE's vision of RDM as a master enfeebler/enhancer.
It's all for naught though if RDM's enfeebles still won't land on the highest-tier NMs. I know SE mentioned this problem in the Manifesto - they need to adjust enfeebles cast by main-job RDMs so that they'll actually land on all mobs from trash mobs up to the highest-tier NMs. It's asinine that my RDM isn't that much better than my BLM at landing enfeebles. As part of its niche, RDM should be able to enfeeble mobs that the other mages cannot.
RDM also generally needs a wider array of Enfeebling and Enhancing spells as the game progresses to 99.
I also like Krab's proposed Job Abilities. A Quick Cast seems like a perfectly logical progression from Fast Cast, but like Greatguardian mentioned, all it would do, as a Job Trait, is annoy RDMs as they end up casting spells in their Fast Cast set. While not amazing, Quick Cast would be somewhat useful as a Job Ability. The 2nd Job Ability would give RDMs a little more leniency in situations like using a MND Club/Shield in favor of a staff for a more potent Slow II or Paralyze II.