Without taking away from anything that's been said here, I'd float a thought about the difference between templates and examples.
Recently I've been working on creating a TBX that will produce a web site/blog and on this and the previous forum there are working links to TBX files that other users have used to do the same task. So as I was starting out I dug these up and looked at them.
What I found was that they all approached the same task in wildly different ways. They also all worked with info differently from how I imagined my own (very simple) project doing things. Still I dug in to see how they worked and tried to adapt them to seve as a base. I'd delete what wasn't useful to me and mark things that needed to be reworked. But over and over I found myself with either a) near-empty files that were basically a blank canvas or b) semi-complete files that I understood imperfectly but needed to be heavily adapted. Ultimately, I decided that I would save myself work or confusion by just starting from scratch.
Once I was well along in my project, those same files were useful examples that gave me ideas of things I might do that I had overlooked working on my own. Using them as inspiration made my own project better. But even then, the examples weren't something I could cut and paste things into my own project. I understand some kinds of actions better than others, and there's no point in dropping things into my project that I don't feel comfortable adjusting. I need to do things using the actions that make sense to me. So what happened is that I'd see something done in an example and would then figure out (usually with help from the forum) how to use "my" actions to do something similar.
What I've wound up with in the end produces the HTML that I wanted exactly and in a browser that output looks very similar to the output of the examples I looked at. But my TBX file is very very different from those examples. Here's the thing though: I understand how mine works and when I've had to tweak things, I'm not at a loss how to do it because it's all rigged up in a way that makes sense to me.
My point in all of this is that the flexibility TBX may make the distinction between templates and examples disappear. Almost anything a user might want to do--if they are going to chose to do it in TBX--is probably going to be something they want to customize. And if that' s the case, then template are likely to function simply as an examples. Which is fine. But if it's true, then dealing with a blank canvas (and all the difficulties that can entail) may be inevitable.
Just my thought though...