Hexagons were already in Lorcana as the ink and exert symbols
We developed a workflow that asked concept artists and card artists to pull hallmark character designs from Yoshitaka Amanos original (and legendary) concept art, the original FFVI sprites, and the FFVI Pixel Remaster character portraits, to synthesize the most consistent elements of each characters design into something new. We also encouraged our artists to punch up finer details and bsexplore elements where they thought they could push (fabric, patterns, textures, etc.) Then, we would meet with the Final Fantasy VI review team, and they would give us feedback on what core elements they wanted to preserve and what new elements they were excited about. "It's our hope that the [FF6] character designs should feel like how you 'remember' them..." So they had the four games decided, but when it comes to Commander, thats only half the equation WOTC also needed to figure out which characters would lead each deck

While not mandatory to play Disney Lorcana game, the mats not only help protect your deck but are elegant and attractive that its hard to picture a match without them
Why its helpful In Lorcana, a character usually cannot challenge an opponent on the same turn they are played