Felix suggested using off-element himes, namely Brynhildr or Nike for healing, but that was back in March 2017. Nowadays, there are healers for every element and every rarity. Buffs and debuffs don't seem to be evenly distributed though, but one should try and make only mono-element teams. So, I wouldn't run Fodla as an healer in a Light team - but she is great for Thunder!

I second Dreamlitz's suggestion of using the Q&A thread for these questions. That thread is more active than this one, so a reply will come quicker.

Also, I am mostly interested in having a SR tierlist, so replies that contribute towards that (such as Nik bringing up Mihr for Fire or Dreamlitz building not one but three Light teams) are greatly appreciated. It will be useful not only for Miracle Tickets, but also for whenever a SR is available in a Rate-Up Gacha or when I need to build SR-only teams for some events.

One quick note: Slashley stated that Dark Amaterasu is unlikely to ever be available with MJ. But Fire Sol is in a Gacha Campaign right now! I will keep hoarding MJ until around the New Year's festivities. Maybe Dark Amaterasu will show up by then, so my motivation is renewed!