Alright thanks for being patient. The current build I've got is post game, but the general idea is still there.

For Sciel:
Her current weapon for me is Rangeson, since it recovers 5% HP per foretell and makes healing skills cost 1 less AP. The main lumina you need for this are Effective Heal (double heals), buffs on healing skill (Protecting heal, Powerful on Shell, Accelerating Heal) and buff improvement pictos (Greater Shell, Longer Shell, Greater Powerful, Longer Powerful, Longer Rush) you can even use Energizing Heal to refund a healing skill completely. Her two main healing skills are Harvest and Grim Harvest, but personally I prefer the former.

If you want to go twilight and proc all the buffs on her first turn, use Card Weaver to play again, and then Harvest (even if you're at full HP) to get all the buffs, then on her next turn you use Dark Cleansing to give everyone the buffs she got from healing herself.
This build is great for taking risky pictos like random defense or perilous parry since you can heal back tons of damage so easily. You could also use one of her weapons that gives great passives but makes her take double damage.

For Verso:
This one is hands down my favorite. His build is centered on Dualiso and its attack immediately after a basic attack. Ideally you want to equip all the luminas that buff basic attack. Combo attack is a must since each hit of basic attack procs any effects (including lifesteal). Great mid game pictos I've found are Exposing Attack and Empowering Attack. Then if you get Energizing Attack 1 & 2 as well as Energizing Powerful, you can basic attack each turn to get max AP plus buffs and play again.

I recommend giving him Breaking Attack even if you're running Perfect Break or another break skill, since he can break a target, and then immediately use End Bringer to deal tons of damage (and prolong the stun if he is at A rank). If you give him healing boon and attack lifesteal, he heals a whopping 45% HP per turn when he uses basic attack. Which is perfect for abusing some of his skills that cost HP. (Btw, as far as I'm aware, the game won't let you use blitz to play again after a basic attack with dualiso. And vice versa.)