I only have experience with these four: Earth 9,5 (Almost perfect, my favorite) HardLight 9 (So much fun, infinity possibilities of dps) Celestial 6 (Op healer and dps, but get boring real fast) Sorcery 5 (Well, he still there)
Might ST: Nature/HL/Celest/Gadgets/Mental are probably too tier Top Tier: Prec ST: Ice/Electric and Rage if you run the gemini Tanks: Earth and Rage are top tier. Ice is a tier below imo but top tier as well on solo bosses.