Peacemaker is a paradoxical chap, isn't he?
The whole premise of the character is that he aims to achieve peace via violently nefarious means. You know, the polar opposite of what John Cena - the wrestler, not the actor - aims for in the world of professional wrestling. It, therefore, makes for an intriguing prospect.
In the context of the Suicide Squad, Cena's work as Peacemaker was superlative, and he'll no doubt have a series of grand performances in the impending Peacemaker-centric television show come 2022.
That said, there wasn't all that much to the character.
Peacemaker spent the duration of the film attempting to one-up Bloodsport. At one stage, they each were innovative in how they mercilessly murdered what turned out to be innocent freedom fighters. A hilarious scene given the context, however, it felt like the only reason for Peacemaker's inclusion in the film was to give Bloodsport a potential threat for the role of the film's obvious main star.
Peacemaker wasn't his unique self here, instead being Bloodsport's shadow. What should have been a marvellous performance for the character was overlooked as a result.