I had an idea for a sequel for FF6 in similar fashion to FF4 The After Years.
The opening of the story:
The fall of the Gestahlian Empire, the death of Kefka, the destruction of the Warring Triad... Those events were part of a prophecy shrouded in dark and light. Had I known of them beforehand, I would have taken such power for myself, I would have become the God they needed, but now is far too late. Thankfully the scars left by Kefka's destruction have been mostly healed, the green has spread through the lands, with all magic gone the monsters have faded into nothingness and a new empire had to be formed to maintain order...
It was to be believed all was well... Until that one day.
Monsters resurfaced near our home in Narshe, the city was evacuated before any causalities, thankfully. However I wonder: How will we defeat those monsters? My mother, Empress Terra, she who choose to watch over this reborn world, has only went me with a couple of guys to help me, both carrying some strange backpack and tools. As for me? All I have is a sword as strange...
Should be obvious by now, the new character is Terra's Daughter. She would start off with Attack, Magi Drain (acts like Runic) and Magitek Blade (which would act like a "SpellBlade", except it instantly attacks on the same turn). As for her helpers, they would be Biggs and Wedge, but not the same from Terra's past, but rather new ones. As such, Biggs and Wedge would have Magitek Gun (allows them to use Fire/Ice/Thunder Beam and Healing Force), Scan (analyzes the enemy). The first segment would be them going through Narshe, up to where Valigarmanda was when the heroes had to protect it from Kefka. There they will find Valigarmanda, who will be the boss fight. As a starting boss, Valigarmanda will mostly use physical attack, and use only fire, ice or thunder when at 1/3 of its health. Upon its defeat, the Esper Valigarmanda will turn into a jagged crystal, which Biggs will confirm to be a "Dying Esper" and that they must take it to the Magitek Laboratory to see if they can revive it.
In this idea, Magicites would not be equippable, because you would want to revive Espers. After reviving them, in gratitude (or debt) they will provide you with a Contract, which of course will have the same benefits equipping Espers had in FF6 (Magic Learning, Growth Modification, Summoning...)
There would be of course different characters to replace the cast of the original.