So, every time they have done a job redesign something feels off. MCH, MNK, SMN just don't have the same flavor as they did before the redesign.

The first question that must be asked is who is the job redesign for? Is it for the player base that has been playing the job? Is it for a new player base that may or may not play?

Why redesign a job in the first place? Technical issues? Design? Or just plain popularity?

The problem is with each redesign they fail to improve upon the core mechanics to that job. MNK was keeping your GCD at 1.5 and positionals. SMN was managing Pets, Aetherflow/Trance, and Spells. MCH was Ammo, Turrets, and Heat post 4.0.

This is important because they could have kept the stuff mains enjoyed and expanded into a direct the developers wanted the job to go. Instead, they chose to remove all aspects of the jobs which in turn alienates the core players of the job.