Arise's opening theme "HIBANA" is "spark". 火花 (hibana) is made up of the words for "fire" and "flower". If you reverse the order, you get "hanabi", or "firework". The lyrics make constant references to sparks and fireworks. Alphen is fire and Shionne is rose (flower). So the opening is directly about them.
But they're not the first fire+flower duo of the series. The first is technically Stahn and Leon. Stahn wields fire, because of Dymlos. Leon wields earth, because of Chaltier. Leon is also likened to a rose multiple times throughout the series, such as his "Rose of Seinegald" title in the PS2 version (and his real-world candle merch that's rose-scented because of that title), and being named "the Black Rose" in one of Link's events.
Flowers were commonly featured in Mutsumi Inomata's artwork of Destiny, but Leon gets them way more often than anyone else. Director's Cut's artwork of them features what looks to be Shepherdess roses (not peonies, since there's thorned stems). The illustration of Leon hung up in a crucifixion pose has pink flower petals floating down. The illustration of Leon and Judas back-to-back also features white roses. Judas's solo illustration has some kind of vague purple flowers around him. The cover for the first volume of the Bruised Memories (Leon) novels has shadows of flowers in the background behind Leon. The second volume has what looks like white daisies or yarrow flowing around him. The second volume of the Recollections of the Bruised (Judas) novels has Leon surrounded by another white flower (probably roses). The third volume has probably white periwinkles flowing around Judas. Mutsumi Inomata's 2004~2015 artbook has an exclusive illustration of Leon watching over Stahn, Rutee, Kyle and Loni with either violet violas or forget-me-not's. There's probably more I'm not aware of.
Anyway, all of that is to say… Stahn and Leon are also firework/spark! And I feel like a lot of Arise's opening can apply to them, too.
Ahh, hey, did you also know? In the Director's Cut artbook, there's a page of all the swordians. There's 5 clusters of them, with all of their blades overlapping. Each cluster has a different one at the center and highlighted. The order of them is consistent across all of the clusters, with Dymlos always being in the middle in-between Atwight and Chaltier. … That's pointless, but I liked it.