With this next version, I have an idea. Currently when using "Basic Tax" plugin it says "country" with a tax drop down for certain countries. I'm located in the USA and currently use the plugin in the state of Wisconsin. We have to set a tax rate for our specific state. So, what if this new version did the following:
1. In place of the name "country" it said "location"
2. Add all 50 USA states to the database
I manually changed and added these features to PayPlans but I'm sure many other USA residence may find use with this upgrade right out of the box.
Hope this helps. Keep up the good work!