Hi @anon870591, thank you for this feedback.
At this time, the new Project Template format is only available to List view projects but our Product team are currently working on building this out for other views (Board, Calendar and Timeline.) This will be available in the near future and I will update this thread as soon as it is.
We have an existing feature request for setting project colours and icons here which you can add your vote to.
Regarding subtasks, you can indeed edit this from the Template Builder which you can see in the screenshot below.
I’m unsure what you mean by the current system making due dates “unreadable”. Could you please create a separate thread in the #product-feedback category for this feedback and I will follow up there? 