at this point I don't suggest you farm that map because of horrible charisma consumption. you might be better off using a dorca/christopher first if you can, until you find another map with alissa.
300 charisma and 6 stamina sunk in trying to get alissa myself. that 300 charisma you can run RtR more than 10 times lol.
of course, you can choose to go ahead and max out the current alissa first, then eventually replace with dorca (you'll eventually need to have 3~4 healers)
so like I said above, you now have 2 options:
1) Max out current Alissa, use until you eventually replace her with another gold/silver healer (and then alissa warms the bench)
2) keep the current Alissa as AW fodder (more on that in the future), immediately rush another healer like dorca/christopher as 2nd healer
just about every map in this event is worth farming except 2nd map that drops alissa, lol. (of course, the G map isn't worth farming either)