For the record...Arena Teams consisting of two Takumis and two Hectors still make me want to smash my ipad, regardless of whatever "nerfs" Nintendo applies.
Seeing as many people pay a small fortune to get rare/limited/OP characters in whatever mobages, it's pretty much guaranteed that no actual nerfs will ever happen to any character. It's either buffing other characters, or more often than not, introducing even MORE OP characters to make other one's obsolete. Which will make people to whale more to get said NEW SHINY OP character.
Seeing as many people pay a small fortune to get rare/limited/OP characters in whatever mobages, it's pretty much guaranteed that no actual nerfs will ever happen to any character. It's either buffing other characters, or more often than not, introducing even MORE OP characters to make other one's obsolete. Which will make people to whale more to get said NEW SHINY OP character.
This is called Accretion. Don't bother balancing anything - just make a new update that renders everything everyone has done up to that point obsolete! If the new stuff is unbalanced, who cares! Just make another update which renders that crap obsolete, too!
Anyway, I'm not quite as scared of Hector. I can generally just drag the battle out so that I eliminate every other unit besides Hector, and I have (ruby sword user) Stahl on my main team, who generally takes trivial damage from Hector.
Takumi's a real pain, however, unless you're explicitly carrying around male Robin or Cecilia (who tends to have kind of crap stats) or other units with explicit type advantage over colorless. Even then, I find suicide-rushing with buffed brave weapon users (like Olwen, who's my main damage dealer, that I keep joined at the hip to Gunter for that +6 Atk/Spd buff) can just overwhelm him. What really throws wrenches into my gears are units with extreme resistance. I have a team geared towards buffing then blitzing with brave weapons, and hoping I can cripple the enemy before the counterattack, and when all but one unit on my team does 0 damage, I might as well surrender right there.
Would it simply be possible to bait and slay Takumi using another archer? I have my own Takumi, so I don't know if that'd be effective, but that's honestly why I always have Takumi in my Arena team. I use him to bait the enemy Takumi, and then just kill enemy Takumi the next turn.
My own Arena team isn't good against Hector, but I don't see him too often, while I pretty much see Takumis all over.
It'll be interesting to see which characters would benefit from inheriting these skills.
I had the fortune of getting my male Robin a Bowbreaker via inheritance, so he stands a fairly decent chance so long as other people don't fleece him... I think.