In my opinion, the "regress" name was not very adequate because regression tests are just a kind of all possible tests: those that detect whether a feature that was supposed to be working has started to malfunction. There are other kinds of tests, such as unit tests, integration tests and stress tests, all of which seemed to be excluded from the project just because of its name.
When I wrote my project proposal this year, I tried to avoid the "regression testing" name wherever possible and, instead, simply used the "testing" word to emphasize that the project was not focusing on any specific test type. Based on that, the NetBSD-SoC administrators chose the atf name for my project, which stands for Automated Testing Framework. This is a very simple name,and, even though it cannot be easily pronounced, I don't dislike it: it is short, feels serious and clearly represents what the project is about.
And for the sake of completion, let me mention another idea I had for the project's name. Back when I proposed it, I thought it could be named "NetBSD Automated Testing Framework", which could then be shortened to nbatf or natf (very similar to the current name, eh?). Based on the latter name, I thought... the "f" makes it hard to pronounce, so it'd be reduced to "nat", and then, it could be translated to the obvious (to me) person name that derives from it: Natalie. That name stuck on my head for a short while, but it doesn't look too serious for a project name I guess ;-) But now, as the atf won't be tied to NetBSD, that doesn't make much sense anyway.