Actually, assuming the same typing and moveset, a Castform evo with that stat spread would be pretty good. That would be pretty nice bulk (especially on the special side) and great SpA. Don't forget that Castform also learns many of the essential weather moves (Hydro Pump, Fire Blast, Thunder, and Blizzard), so it'd have those to throw around. Weather Ball could see some use since no matter which weather you're in, you'll have a base 100 move to throw around with STAB, bar Sandstorm. I could see a Rain abuser set with something like Weather Ball / Thunder (or Thunderbolt) / Ice Beam / Hydro Pump being pretty good. That kind of set up could be really dangerous for key members of Sand and Sun teams, which would be pretty cool.
I really hope they give Castform a new evo in 6th Gen. Even if they just boosted his base stats to 90 each, that would at least make him usable and less of a gimmick.