Blazesoft,
Just to provide an alternative answer to your question regarding assigning templates.
First of all, it is cumbersome to create a lot of plans, assign templates and maintain/administer the plans.
Hence, an alternative could be found in creating a custom template set, with a number of templates in it. This is done by using the Sitebuilder SDK and just thinking of the templates as themes and the template set as the "template".
Seems confusing, but in essence, the SDK provides you with a number of ways of packaging various sites and themes in one template set.
However, restrictions arise in the sense of menu's and master pages (amongst others).
In 90% of the cases, you will not encounter these restrictions and you can offer your customer a number of styles/sites/templates in one custom package.
In the other 10% of cases, there is always a tweak possible: for example, you can make use of nested master pages and menus.
In the windows sitebuilder case, it is rather straightforward.
In the unix sitebuilder case, it is a little more complex. As long as you have root access and xsl(t) knowledge, you can tweak the file template.xsl and add code to make nested templates/menus possible.
Only, be aware that there is always a more simple approach. Before trying to tweak xsl files, first try to imagine whether easier methods are available. In most cases, there are, due to the SDK and the possibility of (simple) custom templates.
If you any questions, just mail...