I notice that some of your templates are based on the T3 framework. Can I assume that you can use just the T3 as the default template?

I downloaded and was using the ZENBASE template, but I could not get my articles to show up. I then made the T3 template the default, instead of the ZNBASE, and the articles showed up, any ideas about why the articles were not showing when the ZENBASE was the default.

You could use T3 but that isn't a joomla bamboo template

The zenbase has two different layouts

as the documentation says

Template Setting - Layout

Layout setting is different compared to ZenGridFramework v2. Initial step is to choose layout:

default - with component output and sidebars
default-home - no component output, no sidebars

This means the home page layout doesn't include the main content area so won't display articles

docs.joomlabamboo.com/joomla-templates/zenbase-documentation (point 4)