The only real standout here is Aggron. It is an offensively-oriented version of Steelix that outputs decent Steel-type damage (though nowhere near that of Scizor or Metagross) and has super high defense and lots of good resistances. It makes a slow but potion-efficient option for Blissey and is especially noteworthy for triple resisting poison and double resisting normal/flying. Even so, it only barely beats a maxed Blissey in time (taking 89-95 seconds if maxed) and is not as usable on defense due to taking 4x damage from both fighting and ground, common types especially with the advent of Groudon. It should primarily serve as a raid anchor or potion-efficient gym option.
Lunatone and Solrock are notable for having double rock sets with Rock Slide, which is superior than Stone Edge. Though they don't have quite the stats to trump Golem, they come closer than Sudowoodo does.
Flygon had very good potential in its amazing movepool. Dragon Tail/Dragon Claw is far better than the Latis Dragonbreath/Dragon Claw, and Flygon even comes with a double Ground set as well as Stone Edge to counter Ice types and flying Dragons. However, its stats are miserably low.
For the most part we are waiting for the rest of the gen 3s. The real non-legendary winners of Gen 3 are Metagross and, to a lesser extent, Salamance.