You say that they're not always declarative like it's a bad thing. Personally, I find it nice that we have the playbooks to build out our infrastructure and the

You say that they're not always declarative like it's a bad thing. Personally, I find it nice that we have the playbooks to build out our infrastructure and the playbooks that perform a rolling upgrade of our application using the same syntax, variables, and inventories. If you keep your declarative playbooks separate from your procedural ones, you get more power than a declarative system alone can provide. (FWIW, we chose it not just for this, but because of its lack of an agent - we can use our configuration management to deploy software to customers' infrastructure without colliding with their own CM.) Further, this (using a data language as a programming language) isn't without precedent. Both XSL and Ant have standard conditionals, loops, etc available for use.