Development often will ignore the aesthetics if the cards are aimed at Constructed and the costs have to be exact.) One aspect I haven't talked about yet is that these designs require that the cards have a value both during your turn and during your opponent's
Jenova will feature in the main MTG set for Final Fantasy at rare, so expect her to show up at your prelease
Shanna, Purifying Blade Shanna is similar in application to Meria, but this time you don't generate mana but health, which is converted into card draw
Instead of Wheel of Fortune, try Wheel of Misfortune or Echo of Eonsthe latter even synergizes well with Lion's Eye Diamond if youre keeping that piece
The Amber/Sapphire deck called Tactical Teamwork has some great Floodborn cards to experiment with as well as some interesting item-focused gameplay
Or you could toss two +1/+1 counters on each dork or Vehicle you control, which is pretty nice as well