I agree with ursboller creating a SAINT classification on the URL variable will allow you to run reports on the 250 specific URLS. This makes perfect sense for the use case that you have described
If you are not familiar with SAINT Classifications, here is a good overview - Overview of Classifications in Adobe Analytics - YouTube
As ursboller said, the steps are (at a high level)
1. Create a new classification against your URL (Admin > Report Suite Manager > Edit Settings > Traffic > Traffic Classifications
2. Download the Saint template for the URL variable. You can also download the template with all URLs captured by Adobe so far. (Admin > Classification importer > Browser Export)
3. Use excel to Add a value (e.g. usageData" ) against the list of URLs you want to track and save the file. (make sure the extension stays .tab)
4. Upload the file into Adobe Analytics (Admin > Classification importer > Import File)
You can then run a report using the classification.
