By having the cards ready, you can immediately start testing new strategies and combos once the set is released
This recent round of previews showed off some versions of Tifa, Kain from Final Fantasy IV, Squall, Rinoa, and Angelo from VIII, Zidane (with one version being an alternate for competitive powerhouse Ragavan), and Vivi, and even a couple of versions of Firion from the divisive second entry
Pre-pandemic, Modern was the most popular format in the area and had more events per week than anything else
Grave Titan, and Cruel Ultimatum were plenty of endgame, the ability to Mystical Teachings up a Punishing Fire was an absolutely crucial addition for being able to combat Faeries and grind out games that went long against even midrange decks, such as Doran
Finally, RW rewards going wide with Inspiring Veteran (although WBs signpost, Wintermoor Commander, also does that)