You have a better group of girls in your water grid than you give them credit for...
I would put you in the same category as my team comps currently tbh. You can either settle for Asherah to have a pretty solid team setup for water, or you could go for Mammon so your average-ish thunder team becomes pretty good.
Given that your other grids are still a bottleneck (and your lack of time doesn't help), and that your water setup isn't too starved of core himes though, Mammon is arguably the better pick, clearly in the short run. My guess for you in the long run, however, is nowhere, you might want to figure that out for yourself
Also, congrats for becoming a useful member of society!