Yes, I fully constructed the templates within the Dorico packages (honourable mention to Bernie Cossentino who did wonderful work with fonts), so I’m close enough to the project that I’m certainly not going to review it.
Each package contains a bunch of templates. Each template contains a predefined list of players (e.g. string quartet, big band, pit band) with a score layout and the usual set of part layouts ready to go.
There are hundreds of tweaks to Engraving Options, a bunch of tweaks to Layout Options (in both parts and scores), plus customised Page Template sets (previously known as Master Page sets), custom lines, custom text fonts etc., all built in and ready to go.
I said I wasn’t going to review it, but I will say that, for instance, I recently used the bulk of the chamber settings (fonts - though chamber are predominantly Academico anyway - part Layout Options, Part Page Templates, Engraving Options etc.) for an orchestral Proms commission that’s being published by a long established, reputable publisher, and their proofreader really didn’t find much. Sure, I still had to consider useful cues, pagination and System Breaks, but I did a lot less manual labour than on similar previous projects.
Everything’s set up for US paper sizes: mostly 9x12 inches for part layouts and small scores, with Tabloid (and in the case of big band templates 11x14), Letter for lead sheet templates (certainly on the Theatre side; I’d need to check for the Jazz ones). But all of the frames on the page templates are constrained correctly, in such a way that if you choose to modify the page size, the frames will still end up in correct places, and all of the fonts that (at least in my opinion) ought to be staff-relative are, so that if you change the rastral sizes (which have been carefully thought through) the right information will scale up and down accordingly. As long as the page size you’re switching to is close-ish to the original, there really shouldn’t be much left to do, though in the case of particularly chamber score layouts and a shorter page height, you may find that you need to either nudge down the space size or reduce the gap between systems in order to get an optimal number of systems on each page.
I’ve not investigated the possibility of actually releasing separate versions of the templates that are set for non-US sizes, but if the demand’s there then it’s a discussion worth having.