Back in the "Old Days," I was one of the more vocal Controller supporters -- I wrote an Earth/Rad guide (and several others) on the forums. You can find it here:
http://web.archive.org/web/20120904193426/http://boards.cityofheroes.com/showthread.php?t=121712
As a secondary, Radiation works well with ALL Controller primaries, it is easy to play with an AoE heal, a single AoE team buff and two of the three Debuff powers are persistent Anchor-based -- apply once and it stays in the Area around that foe until the anchor foe is dead. Conceptually and practically, it meshes well with Earth, too. There are lots of synergies between the sets. For example, combine Stone Cages with Radiation Infection's Accuracy Debuff, and you have foes who can't move around and have trouble hitting you -- almost another AoE control that is available early in the build.
Earth/Rad is a fantastic AoE controller. Earth Control doesn't have a lot of damage, but Rad boosts that damage a little bit. If you have never played Radiation Secondary, then an Earth/Rad is a great choice.
Earth/Storm is another great choice, and was one of my favorite AoE controllers -- Storm has a couple of powers that add a lot of damage. Good synergy, too; Quicksand's Slow and Defense Debuff makes Freezing Rain more effective.
I never tried them but I bet Earth/Time and Earth/Dark are good combos, too.
I was never a fan of the buffing-type secondaries like Emp, Sonic, FF, and others. However, Earth/Sonic is a good paring both by theme (Earthquakes) and synergy (-Defense + -Resistance).
As for Trick Arrow, I think the best primary for Trick Arrow is Illusion. My Ill/TA controller was "Beau Jester" an entertainer and stage magician for the French Foreign Legion. Phantom Army provided great aggro control so I could use TA's AoE debuffs without drawing a bunch of aggro, and the debuffs made Phantom Army more effective. Plus, Oil Slick Arrow + Fireball added something that Illusion badly needed -- some AoE damage.