Wanting to make an Eirika Tactic team

Thinking about something like this. Note that besides for infantry Eirika, the listed IVs are what I have for them.

Eirika (5★ +atk -hp Bless: fire1)
Weapon: Sieglinde
Refine: Sieglinde - Allied Bond
Assist: Reposition
Special: Moonbow
A: Fury 3
B: Vantage 3
C: Def Tactic 3
S: Attack +3

Reposition's versatility is preferred, tentatively. Fury 3 makes her even tougher in an ideal situation, and Vantage 3 makes her a bit harder to approach in those times. Distant Counter could be nice as well but I don't have the resources for that. My reasons for only having one buff skill besides Sieglinde is outlined more below.

Eirika (Sacred Memories) (5★+1 +spd -hp Bless: fire1)
Weapon: Raudrblade+
Assist: Reposition
Special: Glimmer
A: Swift Sparrow 2
B: Desperation 3
C: Atk Tactic 3
S: Brash Assault 3

Just a standard bladetome with BrashDesp setup. She's the one to have Atk Tactic 3 since she instead opts to get her +6 ATK from Ephraim (as well as the +SPD from him). Myrrh and Ephraim wouldn't benefit much from a theoretical Spd Tactic 3, and infantry Eirika gets plenty fast from leeching off her mounted counterpart's buff regardless.

Ephraim (Legendary Lord) (5★+1 +spd -res Bless: fire1)
Weapon: Flame Siegmund
Assist: Reposition
Special: Moonbow
A: Death Blow 3
B: Solar Brace
C: Hone Cavalry
S: Heavy Blade 3

Hone Cavalry is strictly for mounted Eirika. It gives a +6 SPD for infantry Eirika to take up since there's no Spd Tactic 3 available yet, and makes the Atk Tactic 3 the one I want on mounted Eirika since she gets her +6 ATK boost from her brother instead. He also provides a fire blessing in season to beef up the team's defense a bit more, especially useful for Myrrh.

Myrrh (5★ +res -def Bless: fire1)
Weapon: Great Flame
Assist: Reposition
Special: Bonfire
A: Fury 3
B: Renewal 3
C: Res Tactic 3
S: Quick Riposte 3

Def Tactic 3 from Eirika and fire blessing do a bit to patch up her unfortunate IV. Distant Counter would be nice to have but I tried to make a compromise.

Incidentally everyone's from Sacred Stones! Huh. This is more or less a fun team with characters I like that I want to throw together. I'm curious how I can further improve this concept, whether it's about character or skill choice.