they should make Aano her JP version instead of this merc death thingie that you lose sp on...
in an SK file, her being on the field each turn makes her stronger, so why the hell would u want her to return to the file?
u basically lose 5 sp using her skill, and u remove some fast unit. Usually fast units are level 3 to 4. the only ones higher are Bringer and Vondora, in which case a little fire arrow, return, or BOF will snipe her.
so better just make her a tanky ranged attacker like her JP version, and give her her field wiping cross skill. 45 hp and 4 agi sounds ok to me for range 2
