Thanks for your support, people don't seem to realise how much effort goes into this stuff. They complain about spending a few bucks on something they will get many hours use out of, yet the same people happily blow vastly more money than that on things like alcohol, soft drinks, fast food etc.
There isn't really an easy way to offer discounts with the IAP system, i have been thinking about some sort of bundle option possibly but that has its own issues to overcome from an ongoing maintenance standpoint.