"Let's take a simple team utility tank and give him a permanent map entity to micromanage."
The idea of his spirit blade is just not great. I don't want to say it's a bad idea, because Shen having an AA enhancer is good, but Shen having to move this dead weight around the map and try to use it offensively is just silly. Also, why does this come at the cost of his ranged harass / farm skill? He used to heal from his Q, now he has...%max HP damage? Why did he lose a _regen_ skill for a _tank-busting_ skill? I genuinely do not understand what kind of role you're trying to force him into.
His old W has been moved to his passive, which...sure, why not. Having a non-passive skill distinctly for a shield, without any other interaction, IS a dated concept but I'm not sure that's the way to go. Being able to use Shen's shield when you wanted to was nice, imo. Now it's used whenever you blow a skill and then it goes on cooldown.
His new W is just not a good idea. 1.75 flat seconds of AA immunity in a small field...this skill is so insignificant, why is it even there? "In the right circumstances -" sure, but when is that? Do I E-Q-W into a pack of champs? Do I hold onto it to save a squishy? I'm sure it has its uses but I'm sure it's also taking away from his power budget. You should just scrap this skill and use his power budget to give him back ranged farming / harass and healing.
tl;dr none of Shen's new mechanics are particularly satisfying, he's become needlessly complicated with a permanent dead weight map entity, and he's been changed into something that distinctly isn't Shen. Please just scrap this iteration and give us a better rework when you can.