I wouldn't worry until it gets there, Orinsul. The price of the DLC puts more money in the project if you want to buy it. The mods that do things with Islam or add a second religion modeled on Islam (with polygamy, decadence, etc.) could simply make their mod dependent on the DLC. We all had to pay up in EU3 to play mods that updated to the new expansion, but this is better because most of the content will be free; only playing a Muslim ruler is for-pay AFACT.