Adding groups to libraries; Multiple pages per mockup

I'm an interaction designer who has been using Visio for years. While I'm comfortable with it, I'm looking at wireframing tools for others in my 500+ person organization to use. Of everything I've looked at, Mockups is the simplest and most straightforward UI for doing mockups. Plus we use JIRA, so that's attractive too.

There are two features I've read up on here on these boards that I'd like to ask about.

1. My group is trying to get standards and design patterns implemented here. In Visio I've created a couple of stencil sets that implement our interaction approach to things like the accordian, portlets on a dashboard, etc. I want to do that here. I can build everything I need out of the base widget set you've got, but it takes a while. I want to do that and then drag the groups into the UI Library. People could them drag them out where they become a group just like any other group. You wouldn't have to design new properties and options for them because each one is a group of pre-existing widgets. Is this feasible?

1a. As a stopgap, could I build a mockup with my set of standard groupsthat I share with people that they can then copy and paste into their own mockups?

2. The projects feature in which you can have many pages in one mockup. That would be great. Master pages would be great too, but not as important as the multiple pages in one mockup. How do things stand on these features?

Thanks,

Scott McDaniel
Contractor to the National Center for Biotechnology Information
U.S. National Institutes of Health