lol, to be honest i asked myslef the same question at work XD
ended up thinking to just use the advantage element for the events, and when it's dark or phantom/illuison to switch for wind/water depends on skill and use fire during burst time for those element.
for now i'll try to get up the skill levels and make the a little more...balanced.
atm i'm at-
dark 92.5%, fire 90%, wind 87%, thunder 77%, water 66.5% (water missing 1 weapon, so kinda waiting for jack o frost event)
so for now i'll try to get thunder and water to 80% skill level, then both+wind to 90% etc.
i plan to get soul with miracle ticket, so i'll save 3 eyes for her, but aside of her i'm not that sure who should i awaken.
thinking about fire kamihime as i'll be using them during burst time in dark and phantom/illuison events so they can deal more damage but not sure
ID:201799
my main eidolon [last update July 13th]
Having one element as your main is more efficient. For example having a proper Holy grid at the moment is really difficult, so what are you going to use against Dark events? If you have one main element which has 130%+ weapon skills (in total, mostly Assault but also some Defender) you're going to have a waayyyy better time against those encounters.
Furthermore, focusing on one Element will be far stronger when Miracle tickets come around - for those who are willing to pay, you'll be able to also have very ideal team compositions for ONE element. Combine that with having 130%+ weapons skills, and you'll be far, far stronger than having spread your resources around.
ID:201799
my main eidolon [last update July 13th]
130% is 10 SR weapons with level 20 skills - zero SSRs. That's achievable through Disaster farming alone if you're dedicated. And SRs aren't even all that bad to level up, really.
As I said... including Defender weapons. 13% per weapon, 10 weapons, 130%. Whether that's 130% Assault, or 104% Assault 26% HP or whatever is up to you.
The point is... having one capped out weapon grid is really useful to have. Particularly if that's an element you can build a good team around.