|With Weapon Refinery in effect and Bridal Lyn already being the natural, native user of Dazzling Staff 3, giving her the Wrathful version of her signature Candlelight+ should be a completely obvious course of action. Not only does Wrathful Candlelight+ hit decently hard with Lyn's good speed and decent Attack, but the damage it does is essentially free thanks to Dazzling Staff, allowing Lyn to wear down the opposing team with little retribution. Update 2.0 also brought about Candlelight's added area-of-effect status, allowing the staff to apply its special status effect to enemies near its target. Thus, this gives Lyn's teammates an opportunity to defeat whoever they need to without risk of being defeated themselves.
Of course, this strategy still is not without its flaws, as Lyn's offense is still fairly average. She also requires Reposition or Dance support to safely escape or defeat some targets, and competent players should mainly be relying on their other weapon users to defeat the opponent. It should be noted that against teams with a focus on armored units (aka Armor Emblem), this set is essentially a free win against them as armors have low movement and cannot hope to keep up with Lyn if she has teammates with movement assists.
Rehabilitate+ is still a great healing skill despite being underwhelming compared to other premium heals (especially Martyr+), as it instantly restores almost all the health of near-death teammates. It also comes natively on Lyn, so there's little need to change it for efficiency purposes. The Special slot is mostly flexible depending on your needs, but Lyn has access to both Imbue and Swift-Winds Balm by default. Since premium Rehabilitate+ has no cooldown, you can essentially afford to run any Special depending on team needs.
The A-slot passive skill serves to improve Lyn's overall offense or speed. For general purposes, Speed +3 may be preferred, especially with a Speed boon, as it enables Lyn to achieve more doubles while preventing others from doubling her. It's perfectly serviceable for Lyns of other boons, though if you're not confident in Lyn's ability to double, Attack +3 improves single hits. Lyn can also increase both stats with Atk/Spd 2, though, let's face it, the average person probably isn't sacrificing a Nephenee just for this.
The Sacred Seal and C-slot are also flexible depending on team needs. If you prefer Lyn to act as a more independent unit, she can equip Savage Blow in either slots or both for added free passive damage. A flat boost Sacred Seal such as Speed +3 can be used to cover weak spots in Lyn's stat spread, or overkill her Attack or Speed to deal more damage. In the realm of supportive skills, she can also opt for Hone or Fortify boost skills outside of Hone Speed, as Swift-Winds Balm already boosts Speed.