What I prefer about ansible above all others, besides its simplicity, is that its use case scales up and out. By that I mean ansible can be used for platform/app stack provisioning while OS/infra sys admins maybe another tool. To often an agent based approach causes a conflict with OS sys admins and platform/app team regarding ownership/sharing. I want to offer self service as much as possible.
Further, most cfg mgmt tools are monolithic in that they want to manage all servers as tho a single team/overload manages them all, rather than various independent sys admin teams. With various independent teams its just too much hassle trying to share roles appropriately or setup separate master/agents.
Ansible does not have these issues.