This is probably one of the worst suggestions I've seen on this forum and I have to congratulate you. Lightning is one of the best jutsu in the game because it's one of the few jutsu that have a guaranteed 7 combo string with lightning cutter. Reducing the cast time will make it impossible to dodge and will create guaranteed damage of over 700 damage just from a single jutsu.
Nerfing Earth Prison while buffing Lightning Cutter and Lightning Pillars is pretty stupid. Instead I'd suggest changing the way targeting works in the game and allowing Earth Pillar to snare less people and instead base it on who is being targeted by the player. Rebalance to Substitution is also another bad suggestion. If you're looking to buff lightning which includes 3 homing techniques and you're complaining about Replacement I think you should instead focus on your own gameplay as that's the issue.