I’ve already modified the plugin to the point where I won’t be able to upgrade. But it was a pretty easy fix. Other changes I’ve made or will be making:
1) Add an impressions counter
2) Add a max impresssion setting
3) Add a fallback feature (rotate certain ads when no specific target add exists)
4) Add a log for verifying its working properly
5) Add start and stop dates
I’ve already done 1) through 4). Its not difficult. Your plugin is pretty easy to follow.
You need at least 1) and 2) to make your plugin commercially viable. You have to know how often an ad is viewed even on the smallest of sites.