Ishtar IVS?

I don't know if a battle simulator is really a reliable source for determining the best IVs/skill sets since you'd have to manually enter in every unit's most preferred IVs/set to get the full effect of the battle simulator, and that's a bit tedious.

As for which one, I'd think neutral is better, but a -Spd Ishtar is workable, considering she gets +10 speed on initiation. Guess it mostly depends on preference.

I have a +ATK/-SPD Ishtar as well and I am absolutely OK with it seeing she still gets 43 SPD on initiation. She could get doubled by fast mages on enemy phase tho so just slap a Initiation Speed Seal if you want. Honestly, she is a great candidate for regular stat+ sacred seals so this ends up working out perfectly.

+atk/-spd isnt too bad. initiating attacks at 43 speed is still pretty high.

I am using a +def/-spd Ishtar (fml) on the arena as the bonus unit everything seems fine, and with the bonus stats for being a bonus unit its 37 base speed. outside arena ill just probably team her up with legendary lyn having speed tactic.