i think u have come very close to diffrentiating between the 2 ideologies however with one excption.. ahle sunnah regard the first 30yrs as rashidun caliphate meaning that it was guided by people who were most knowledgable in religious knowledge of their time.The decisions taken during this time by ijma of religious community they look upto as religiously and legally binding. Unfortunately with the start of kingship the leadership of community from religious people was lost , the decisions taken by these kings are never regarded by ahle sunnah scholars as legally binding ...infact many ahle sunnah imams were persecuted by their opposition to the decisions of kings.But since these scholars also represented the mainstream religion of their time they had to temper their criticism so as not to elicit a very heavy handed response from kings/tyrants. 12er and other ideologies did not have their obligation, they cud concentrate more on the "perfect scenario" and theoratical aspect of their ideologies.But when 12er religion was put into practice in iran and awadh they ran into the same problem the churuch and state had to be seperated as they cud not ever get a king who was religious enuf to be both.Infact before 1977 -79 12er clerics discourgaed participation in political matters ( until imam khomenini came along with his concept of velayat e faqi)
Exactly, I fully agree with you. This issue will stay unless we have a God appointed leader that can bring it back into a single person, the "Mehdi". Mehdi will be the Imam/Caliph/Leader that will solve this issue by being the political and religious leader, and if you are mainstream muslim sunni or shia, you probably won't disagree with me.
Ever wondered why can't we just chose him out of Ijm'a?