If they did something like a rune knight, it'd be kind of cool if it was similar to how runes work in the game Outward. The gist version is you combine runes for effects, which already exists for ninjitsu. Instead of just using runes, it could also be something like 4 rune sword moves with individual combos instead of just standing there doing combos. That alongside the hardcasts mentioned above and it'd probably be an interesting job without being too difficult to implement. Definitely wouldn't be the same as what we have now at least.