Gala Elisanne seems to me to be a very solid character that won't really make a splash right away because the kind of party she wants to be in for endgame doesn't currently exist.
Thinking in terms of mHBH, where the standard composition is S!Celliera/Elisanne/Lily/Thaniel. G!Elly wants to take the baiter spot, but then you'd be left with two buffers and only one DPS (and Lily isn't exactly a top tier DPS) so you're losing out. So you think to maybe drop regular Elly as well to add another DPS, but looking for a Water DPS who isn't a baiter (so not sword/dagger/axe) you're left with... not much. Regular Celliera is probably the best option here, and she has seen some success in mHBH, but she leaves a lot to be desired.
You can also use Chocolatiers G!Elly to not have to bring Choco Thaniel, but then what do you even replace him with? Thaniel could bring a healing print, but he doesn't really need extra healing in mHBH. (the healing requirements are actually lower in Master than in Expert) You could bring Nurse Aeleen, but she has the same problem where you don't really need the extra healing from her.
What Gala Elisanne is looking for to really be a force in mHBH is a strong Water DPS that uses lance/blade/bow and a new Water healer that say comes with a regen S1 and some kind of buff on S2. Akasha is the type of healer I'm thinking of here. The leak/rumor says that Xainfried is getting his 6th mana circle next month, so perhaps he can fill the first slot. Last year's Christmas units were Water so I assume the new ones we get this year will be a different element, like how the new Halloween units were. Perhaps our new set of Hinamoto characters for the Year of the Rat will be Water.
mHBH teams are really going to be looking for an excuse to drop S!Celliera since her S1 inflicting bog kinda messes things up. Like the other Master fights, mHBH can be inflicted with bog exactly once, and that chance gets wasted with S!Celliera (or S!Julietta) on the team. On the other hand, teams without those characters can safely use Leviathan to inflict bog right before break and really hammer the boss.
So I don't know if Gala Elisanne is going to be super popular in the near future. But I have a pretty good feeling that six months from now she could very well be the cornerstone of mHBH teams.
