You did not do your homework. There are only 3 true religions (Al-Islam, Christers and Yahoodis). Deism, like polytheism is a human invention, that was not even worth mentioning in Al-Kitab.

Kufr is from Iblis, so it is from a more powerful source than so called deism. There are only 2 parties: party of Allah and us (Al-kafiroon). Anyone who was a Muslim and then changed their religion is a kafir, as they know that Islam is true but reject it out of pure evil as far as Al-mu'minoon are concerned. In other words, you must choose: either you're with us (kuffar) or you're against us, there's no deism option. This goes for Sophia as well. Peace.
That's absolutely right brother. In fact I've heard that Lord Herbert of Cherbury who founded deism was one of the djinns of Iblis, and when dajjal comes out in the end times he will preach deism or atheism. Its possible that he is already out in the form of richard dawkins.
Also, yajooj majooj are followers of deism as well. And on the day of qayamat, trees and leaves will say 'o muslim, there's a deist behind me, kill him.'