Geo's nuking is actually in a pretty good place atm once you're geared for it. Stonera II > Stonera will kill pretty much anything in Skirmish, Stone II will one shot any magic weakness mob, 4-5 Stone Is can kill anything else, Stone IV will one shot most non-magic weakness mobs, etc. Its funny just how massive of a difference gear makes with nuking. Nuke in idle/Geo gear on accident, Stone does like 40 damage, toss on gear, 1100+ lol. -Ras are still far from MP efficient, but they kinda feel balanced when there's 4+ mobs around to hit.
Its actually pretty powerful now, though I'm not certain how this'll play out in alliance content. Its currently helpful (but far from needed) on most Delve NMs. Spamming Thunder I on the final 25% of Daqu is pretty entertaining, for example. Be careful not to pull hate and pull him outta place during a Mayham! ;D