Help Me Theorycraft My Fun Arena Team

I went WAAAY harder on the new banner than i intended to, thanks to a particularly good night. Ended up pulling 2 Ephraims, Seliph, and Julia. Excepting Takumi, loliTiki, Lyn, Hector, and Azura, assume I have everyone else. It's either true, or I'm just waiting on feathers for it to be.

Anyways, now I kinda want to make a team using at least one of them. I've already got a team at the 4500 mark, so this is just for fun. Naturally, Ephraim makes the most sense to use out of these 3 IMO.

Team Member 1: Ephraim

Pros:

• Hits really, really hard.

• Naturally high Defense

• Meta is full of reds, and he slaughters the lot

• AOE defense debuff

• AOE damage buff on attack.

• Discount Luna that is up nearly every turn

• High stat total for Arena

Cons:

• Low Resistance.

• Debuffs don't stack

• Terrible speed; doubled by most threats.

So, here's where the fun starts. Ephraim doesn't have the freedom of mobility to kill reds with impunity, even though that is clearly what he wants to do. Olivia would remedy that, but I want to try something a bit more fun.

Slot 2 will be either Catria or Sharena. Why?

• Catria has mobility and safety to attack targets that Ephraim can't get to.

• Sharena actually has a complementing set of buffs and Debuffs. Yes, there is a ton of overlap between their roles, but they kind of become a tag-team duo of death whenever they are near each other. Sharena is also currently featured in Arena, but who knows what'll happen next week.

Neither address Ephraim's real flaws, but both allow Ephraim to do what he does a little better than he would otherwise. Catria protects from mages, Sharena makes him laugh at physical attacks. I think both would be fine choices, but feel free to weigh in.

Slot 3 will be either Julia or Nino. Switching to a third listing format...

Julia:

• Counters Nowi or Corrin F. Nobody runs Fae, and the Tikis aren't as big of a threat to Ephraim or my Slot 2. She'd still soften them up.

• Hits Robin and Linde, the two most common mages, hard.

• Has some minor healing to help keep the team healthy.

Nino:

• Greatly appreciates the buff AOEs of Ephraim and possibly Sharena.

• Also sticks it to Robin and Linde

• Has a better +ATK AOE than Ephraim, and also gives it to him.

• Draw Back provides some added safety

Nino would need to be promoted still, but I'm thinking she'd probably do just fine at killing Nowi. What makes this a toss-up is that I'm not sure how necessary the dragon bane effect is. Nowi can't easily kill Ephraim as-is, but she does damage. Nino would kill Nowi just fine, but its still a decent amount of damage taken. I might use Julia until I promote Nino...

Slot 4 is the tricky one. There are two major threats I still need to deal with: tanky greens (basically Hector, maybe Minerva,) and Kagero. I also lack any real mobility options on this team. There are a bunch of units I'm considering for this slot. Yay! More lists...

• Lilina - Much needed ranged attack. Should kill Hector or Minerva juuust fine. Unfortunately, does nothing to stop Kagero, who is easily the biggest threat if I don't run Catria.

• Roy - Hector becomes a non-issue. Does nothing for my issues with Kagero or range in general. Pushes stat pool total for Arena high.

• Kagero - Who better to take out neutral threats than the best neutral threat killer? Mine's even +1. Unfortunately, does nothing for Hector.

• Merric - Hear me out. He actually does fine vs Hector or Takumi. Won't kill them outright since he hits like a wet noodle, but he'll weaken them enough to kill without being devastated in the process thanks to high DEF and HP. He also gives Ephraim some added survivability vs mages, which is a huge boon (also gives Nino more damage if I use her.) Still does nothing vs Kagero.

• Gordin - Will kill non-HP or DEF boon Takumi in one round with an ATK buff WITHOUT being countered. He's actually a player phase ranged terror that will kill most other ranged threats, save Robin and Merric, safely. Also has shove and vantage for some utility. Unfortunately, gets doubled by almost everyone and will almost never get the quad attack without a speed boon and buff. Also, does almost nothing to Hector.

• Caeda - Kills Hector with some help via buffs or what have you. Also can give speed when needed, boost the team's RES, and has flying to hunt down Nino or Kagero. Takumi wrecks her, though, and her attack stat sucks. She NEEDS buffs to kill.

• Laslow - Once again, kills Hector. Gives other units needed speed. Not much else to say; does nothing for problem vs Kagero or the like.

• Seliph - He's not doubling anyone without activating Brash Assault, but he's not easy to get killed. Also, being mounted means he doesn't have to fear Kagero AND he has enough movement to get in the face of squishier enemies. Unfortunately, Linde, Nowi, and Robin will murder him.

• Lucina - Is Lucina. Won't deal with ranged threats, but is otherwise stellar.

I know this post is a stupidly long way of saying this, but TL;DR, I am looking for some input on choosing a character to do a very specific job. That job is to kill Hector and/or Takumi/Kagero. Input is highly appreciated. Discussion is encouraged.