They don't seem like they're going to be that much better frome everything I've read, and quite honestly, from what I've seen they're just pointless. x_x; Like what's already been stated here, it just looks like it's going to be more classes that throws RO even more out of balance than it already is, and with the achievment of trans. classes, the balance is nothing close to being good, especially when it comes to private servers and the HR/SHR. I think the third classes could very well possibly work on LRs, and maybe MRs if the data is seriously worked on to put everything in balance with them.
It would've been okay if they would have kept the third classes only accessible through second class, but if they're now going to be able to be obtained through trans., then I would say no to them. The best idea is to still give everyone who's worked hard on trans. classes to still have a purpose for them, rather than have to start all over again.