I personally prefer that with Pandocomatic (or Panzer), I use simple YAML metadata for templating. The syntax is clearly focussed on Pandoc so it is very close/identical to the Pandoc command-line settings/metadata. I like tools which are made for the job, and that have a very clearly specified interface (pre/postprocessors etc). 

For people who have never used make, then it is *much* easier to explain YAML metadata to them.

But if you look at something like Pandoc-Scholar[1], then you see an elegant makefile useable by non-experts can do what these specialised tools can do, and though the makefile is more verbose perhaps than pandocomatic, it is bound to be more flexible.

Ian

[1] https://pandoc-scholar.github.io