Ranked shen works most in lower tiers(bronze,silver,gold) even thought he is used in bigger tiers but in them he isnt used that much cause of him not being that strong in meta right now.

Pros

-great teamfighter.
-good split pushing (with right items).
-nice substain.
-escape.
-shield.
-rewarding you for building defensive (hp).
-good late game hyper tank.
-incredible peeling and protecting carries.

Cons

-hiting E and R is crucial.
-doesnt snowballs that hard.
-%damage destroys him.
-ítem dependent.
-not best laning either.
-dont carry as hard as other champions.

Summary
Shen is very strong champion as he was long time ago only problem is that meta isnt too good for him right now (rhm gnar) he is still viable to play but he wold need buff to his damage to not be meat shield and be something like gnar is (too many references to gnar sight).