The old Shen kit was much easier to use than the new one, which actually increased his skill ceiling. Almost everything that old Shen can do, new Shen can do as well, but would require a bit more effort.
I do miss the old Vorpal Blade Q, since that allowed a simple method of sustain in lane, both in solo lanes and support roles. It also was a ranged attacked, which gave Shen more flexibility. It was also what allowed Shen to be a decent support; he could harass at a slight range, and offer some healing to his laning partner, two options that the rework removed.
However, the new Shen looks to be better than the old kit in terms of his role as a tank. Spirit's Refuge (W) can mitigate more damage than Feint (W) would without building for AP (and who builds for AP on the old Shen?). At best, Feint can help protect against a single autoattack or the last couple ticks of Ignite. Spirit's Refuge completely blocks all autoattacks in its area. This actually allows Shen to tank notorious auto-attackers, like Yi and Xin Zhao, and still live to deliver the third hit of his Twlight Assault. Getting Ki Barrier to proc during all of that is just gravy.
I figure that the reason not many people play him as much as before, and his low win rate, is that he indeed has a higher skill cap, and requires more than just a passing familiarity to be successful with him. Additionally, Shen is a team-oriented champion. Sure, he can be effective on his own, but his kit is fully realized when he works with the team. His two signature abilities, Shadow Dash and Stand United, demonstrate just that. If his team is not doing that well, then Shen himself might not be doing well, too.
My only real regrets with the remake are the loss of holding two swords (ala Leonardo from TMNT) and that the remade Blood Moon skin doesn't look as awesome as the pre-rework version did.
