Alright IVs I guess. Should I still give him a defense based special skill like Ignis or Bonfire, or Keep Aether on him? Also, is it a better idea to give him Quick Riposte or keep his Beorc's Blessing?
Keep Aether, it works really well with Steady Breath, QR is awesome on him, because he will keep getting healed from Aether putting him in the range of it again. Here's mine (He's +Atk -Spd). This set works really well for me, and I hope it works well with those IVs. I use Beorcs Blessing for the Arena for more points, and so he can fight Cavalry teams.
I've recently added the Attack Smoke Seal to my B!Ike and yesterday I marched him into a group with one red. A bow user attacked first, for nothing, and then the red hit hard but didn't kill and by this time Aether kicked in and healed him well enough to sustain the rest of the enemy team which did piddly damage. I forgot to mention my Ike is -hp+def and summoner focused and supported by Delthea so he's an absolute monster with an effective 48 defense or something ridiculous like that, plus the +6 atk from Delthea (Ike gives her Hone Speed). I will bait anything but a red mage or a top tier sword with him and walk out alive and a huge part of it is the seal.
For those that don't know off the top of their head what the Attack Smoke Seal does, when an enemy attacks Ike, any other enemies within two spaces of that attacker get hit with a -7 attack debuff, allowing him to shrug off most followup attacks and keep his health well topped off with Aether.
TL:DR - To answer OP's question, Aether charges if you take two hits. Combine that with the attack smoke seal and most units won't do a thing to Ike except heal him. Your mileage may vary, my Ike has +def and I hear good things going +res even.
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