Sadly I only have one Eunice, Can't remember what I did with the other ones. Though I do have two other mortimer's.
With Imelia I managed to Cost reduce her to the same cost as Lyla, was still building my team during that event so I was working a fine line between the event and leveling units thus why I only got her down -2 points. I got 300 Souls during the event so got her skill to 4/10 and -2 cost reduction.
So by the sounds of it my Imelia and Lyla are pretty much head to head in terms of stats but seeing as I have a head start with Imelia in terms of her skill and she will be more of a benefit due to that skill she would be my best option.
I will level her then and when I get around to it, I will work on either Mortimer or Eunice. Thanks for your input!
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Yeah I only managed to CR her to the same cost as Lyla and at the moment guess I would be seeking a Tank rather than DPS, though I will be wanting to lvl her up later, just after the better choice one at the moment. Thanks for your input!