Well I love a bit of theorycraft so here's my suggestion:
MAXIMUM REFLEX ROINA
| Ravian | Yeon | Nari |
| Bell | Roina | Lynia |
| Aslan | Milky Way (ace) | Defender/Totem |
| Serestia |
Victoria CM support
Roina has a 40% reflex passive and great base reflex for an attacker so let's stack as much reflex as we can. First we gotta place her CM because she's the star of the team (and max position bonus). As for stones, double ardor reflex is a must. Teranox or IC for unique plus dark crit dmg/pen.
-Midline- Bell, Victoria and Lynia give Roina 105% reflex, 55% attack power, 25% action speed. You can even put Silent Cold on Bell/Lynia and EBM on Victoria.
-Backline- Aslan - another 30% reflex buff for Roina Milky Way - her ace gives 25% reflex and AS to Roina and when she pens through to mid, guess what? MOAR REFLEX Kevin - needed for Milky to move first in the back Serestia GK - ok so we have IC on Serestia and she starts with 80% action bar thanks to Kevin. Nobody will outspeed her without action bar shenanigans but Roina will kill MetaBeth first so we don't need to worry about this. Serestia uses active to disable their striker/assist and debuffs the enemy team's reflex.
-Frontline- Ravian - Ravian's job is to lower the enemy GK's hp with Gravity Down so Roina can finish them off. Could probs use a different striker if you wanted. Nari - Roina has a rival chain with Nari. 10% more reflex but chains affect base reflex so she will gain more from buffs too! Stick IC on her. Yeon - Yeon is our EBM holder up front. Her job is to get killed so Roina gets +15% reflex. Well it's a team game and you gotta make sacrifices for Roina.
WARNING: If you ever meet Lord Vann using this formation, start crying and beg him for forgiveness or he will destroy you with his action bar powers.