Actually, they have. Acrofighter (AF) and Acrotecher (AT) are the two newest classes, and I guess Hyperguy wasn't around when Protranser (PT) came out, which was quite a while back... =/
Anyway, the Acro classes have faster attacking/casting speeds and specialize in one-handed weapons, notably the new Madoogs and Shadoogs, which resemble the Mags from PSO, as well as the new slicers and whips. I haven't tried out AF yet, but I'm loving AT, especially with my Har/Quick equipped. Compared to Fortetecher (FT), AT's have access to higher-level support techs and have faster, weaker techs, while FT's have access to higher-level attack techs and slower, stronger techs. Since AT's can't use rods, Sonic Team actually had to give FT's a 20% buff to rod weapons simply because AT's were outdamaging them through sheer speed alone... O_o;
Protranser is sort of the "Red Mage" type of job that dabbles in a little bit of everything, but uses melee and ranged attacks (no techs), and specializes in traps. It's one of the most difficult jobs to level, simply due to their low stats, but PT's have become more popular now since they have exclusive access to the new EX traps, as well as all S-rank weapons (pre-AoI, it was all A-rank). There's also mention that PT's can also see hidden traps, similar to how CASTs could in PSO, but there still aren't that many missions that have them...
Here's a link to a link to all the class updates as of the AoI expansion:
http://phantasystaruniverse.com/game_guardiantypes.phpAs far as the old PSO content returning, I've heard that Japan has recently had an event called "Max Attack," which featured retro-style missions and items; no word yet when the US is getting it, though. There are still a few old school elements to enjoy, though: Boomas and Grass Assassins make appearances on some of the new missions, and weapons like the Durandal Replica, Varista, and Nei's Claw are available now.