so a lot of people seems to be under the assumption that nothing can be done to fix the mudra delay because its based more on your isp than what SE can actually do, but there is a few ways it could be done to work with/around the issue.

first off being move the mudra registration to client side, meaning the icon and executed skill will be determined by the client, but then confirmed by the server (which happens anyway right now), this method would enable players to execute the correct ninjutsu with minimal delay, baring any significant lag spikes from affecting the mudras themselves.

another option is to allow skills to be executed between the final mudra and the ninjutsu cast, or between each mudra, therefore lessening the effective downtime caused by the latency.

it would be good to hear from other players on the above possibilities, and possibly some other potential fixes, with enough luck (and posts/likes/views) SE will read the thread and hopefully use one of them for the game.