Water (Best element, can heal/debuff/buff/spike damage,
requires later KH that you probably won't have for half a year) >>>>>> Fire (Glass cannon element, lacks survivability but a lot of SSR event weapons to support. Amaterasu will be a godsent if you have her.) = Dark (Only if you have beelze, else goes behind Thunder) > Thunder (High spike skill damage, can paralyze boss, also offer some debuff. Not much healing exist) > Wind (Multihit specialist, burst gauge filler, your only debuffer is literally Oberon which is a SR. Gaia boost your team survive rate by LOTS) > Light (Literally good for nothing, lacks debuff, lacks damage, lacks event SSR. KH skills are all over the place. Sol is god tier KH but you better off splash her into other element team. The dev are trying to buff this element right now it seems.)