The thing is.
With all the non-W's he collected (Vergo, Doflamingo, didnt have a single 1v1 against the more threatening enemies in WCI), no sign of developing CoA beyond the basic, it would be a tough pill to swallow for him to suddenly beat a YC for example.
Oda gave him the suit to compensate for this gap he let the character sink in.
And immediately sends him into another Kalifa gag situation.