Integrate large sortable database with regular flat-file (csv) updates -- Is CCK + Views the right recipe?

Hello,

I am working with a small nonprofit organization helping them migrate an old static/piecemeal site into a CMS. We are quite confident that Drupal is the right tool for the job, and I already have intermediate Drupal experience. We have mapped out most of the necessary specifics for their new Drupal framework, and related content migration processes, but there is one element from their current setup that I am not quite sure how to handle with Drupal, and I am seeking any insights I can find.

Their current site has a feature/section called the "payroll database", which is a simple listing of salary information for various government offices (made available by the Freedom of Information Act and part of their mission to encourage transparency in government). Site visitors can view, in a small table, a listing of salary details for government employees based on their office (each row contains "employee", "position", "salary", etc. headings). Currently this is powered by a custom ASP script and a MSSQL database. They populate the actual data via excel or access files provided by government.

Getting this running in a new Drupal site would seem trivial for CCK + Views, but I have the following concerns:

• This payroll database will grow to literally tens-of-thousands of entries. With CCK + Views, each of these would be a node, and I fear that so many "payroll" nodes would be tricky to handle (admin and maintain) within a site that otherwise has only has a few hundred nodes of other content types.
• We need an easy way to import large volumes of this payroll info from something like CSV flat-files, on a regular basis. I can't find a very easy way to do this with Drupal 6 (all other site specs point us to v6), and it seems that the "node import" module does not even support CCK-types for Drupal 6 yet.

On idea that came to mind is to run this payroll database in a separate Druapl 5 site (perhaps on a separate subdomain). This would, in theory, address both of the concerns above, as it would isolate the payroll content in a totally separate system, and furthermore, the "node import" module for Drupal 5 will support CCK content. But if we go this route, I'm not sure how to integrate data between the two sites in a useful way (or if that would even be possible).

We are hoping to avoid the need to hand-code this payroll database feature, as there are obviously a number of advantages of getting it running within a Drupal installation (scale, future feature additions, etc.).

We would really appreciate any insights or pushes toward other modules and recipes that might work. Many thanks!

Ryan