I personally think that RDM is fine where it is. It's nice to have a solid dps that is easier to use. I finally can worry more about mechanics and things happening in a fight without staring at my bars. It also allows me to be able to keep an eye on my party members so I can throw a clutch heal or rez in quicker.

I don't know anything about Summoner, but it sounds like the concensus is that it should be equal to RDM if not slightly ahead. I'd be fine with that.

Black mage should definitely be buffed to do more dps than RDM.

I wouldn't stop playing RDM regardless of what happens to other jobs. I would just hate RDMs to get nerfed and take the chance that the community sees them as useless despite it probably not being that hard of a nerf anyway. Fix Black Mage and Summoner, then take another look at everything.