I second https://paperlex.com. I was at GA/NYC a week or two back when they publicly demoed for the first time. It was very impressive. Think markdown for legal documents. The most interesting thing about it, imho, was not the structured templating but the counter party signature mechanics. All done online and driven by the data in the document.

As somebody who knows and have done work for the Paperlex guys, I can genuinely say that they have a really interesting product, and the guys running the biz are bright. I think they're going to do well.