When I put this together I was more concerned with the functionality rather than the aesthetics. Most people run the file through a cron so I didn't think that having a back button was that important. But this is planned for future versions. I really only added the manual ping feature because there are still quite a few people that have no clue what a cron task is.
1. When running Plingger it should run in a normal template window, providing navigation controls so that the user doesn't have to user the back button.
I wanted it to run in one process. This cuts down on server load and would make the user have to set up a multiple cron jobs for each server. If I had done it that way.. People would have complained to no end.
2. It should attempt each ping in turn and write back to the page whether it succeeded or not instead of waiting till it has completed to display any feedback
Once again this was intentional. I wanted it to be simple enough for anyone to use and also to keep the database server load down.
3. Instead of keeping the list in a text file, the list of sites to ping could be in the database.
While this does sound obvious, and is planned for future version it was also intentional at the time. It basically adds a weak point when thinking about security.
4. One could edit the list of sites to ping through the admin. interface.
Hope that clears up any confusion.