who do you think is the Most Intersting Arabic Caliph?

Umayyads were great rulers too, but Ali was better than Moawiyah I think.

Infact it was Umayyads who turned Arabic state into a real empire but again they failed so quickly. Ill fated campaings against Franks, Romans, Khazars and Turgish weakend their positions in Khurasan especially. But again, anykind of Empire will at the end have ill fated campaigns. It will not harm the statesmenship of the first Umayyad Emperors.

Ali would be better as a Caliph instead of Moaviyah because, you know sons of Ebu Suyfan were not really muslims, drinking alcohol, etc...

We are discussing religious matters so Ali over any of them.

Umar Ibn Hattab, Moawiyah, Haccac were great statesman, but I do not think they were great religious leaders.

Since I see both Sunnites and Shiites like Ali; However, Shiites dislike Umar.

But, yes Ali would make a great leader too, since he would have good lieutenats around him.