This actually triggered me. Are we like year behind, when "either you have debuff or go home" ? Thunder got Noel for free (sux if someone missed event), thunder have amazing Cyclops, Gryla is quite decent, Kingu is really strong single target tank and many of them can dish quite ok damage. Times of "thunder's bad SRs" are long gone.
On a side note, now that I look at it, almost all mentioned SRs by me have debuffs (that's not why they are good though).