My favorite character was my Plant/Storm troller - the secondary worked just fine for me. Besides, I never went for the most effective builds - I always went for concept.
My Earth/Storm was a lockdown/knockdown/procdown death machine against most enemies. Not as fast as some Controller builds, but nothing below AV/GM level had a chance. With a few procs in Freezing Rain and Volcanic Gases most spawns just dissolved without a chance to retaliate. Tornado could rack up some impressive damage against AVs as well once the trash was cleared out.
For sheer flair my Plant/Dark was my funnest and creepiest alt at the end. (Just the Carrion Creepers noise alone as it followed me around invisibly...
)
Still, powers i'd never want... Lighting Control: all you can do is make it brighter or dimmer although a few powers can stun enemies and induce seizures in other players. Lighting Blast: lots of stuns and -perception effects, but all the powers below the tier 9 power, LAZER BEAM, do Force Bolt level damage. Edit: Hmm, Build Up equivalent for Lighting Blast, IMA CHARGING MY, adds a DoT damage proc to the tier 9 in addition to the damage boost.