Can and/or should I still try to make the best of this or should I hope to get another one?
With Spoopy Mia, you're mostly just going to want to attack with a Dazzling Refine and mess with foes' cooldowns, IVs aren't that important here, or on most support units in general.
You can go for another one if you want, but your current one is still 100% usable.
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Now if you wanted to go for Wrazzle Dazzle that ORKOs things instead, you'll definitely need to pull for a better one.
At budget, base kit will do for Spoopy Mia, for a B-skill you can go for some standard options like Live to Serve. But because she's a flier, she has some other options every other healer currently in the game doesn't have.
As an A skill, budget skills can include Attack +3 or Speed +3. 34 speed + Hone Fliers support allow her to reach 40 speed, still good for mage survival and avoiding doubles. Some more expensive options are Atk/Spd Push and Atk/Spd Bond for offense. There aren't too many notable defensive options, however her default A skill will work fine.
B skill can vary. As a flier, she can use some skills other healers can't. Flier Formation and Aerobatics help with mobility, which can be used for getting around better to heal others. You can still run the skill that opposes the refine if you want, too. Otherwise, a cheap basic option is Life to Serve.
As a C skill, Hone Fliers is rare and she has it by default. I suggest keeping it if you're putting her on a flier team. Otherwise, Tactic skills will work nicely, Atk Tactic is available from a 4 star Legault.
I recommend looking through all of the possible skills healers can learn as well, bit those are all some pretty good options, I feel.
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