Solmyr said:- Changing the Emir title would mess up various existing Muslim duchy-tier nations that are ruled by Emirs, which is historically correct for them. So it's best not to do it. If there is a smaller title to replace Sheik then you could do it. Perhaps Qadi?
Qadi is just a chief judge, the highest officer, but never a ruler. Rulers were of noble origin and had military training while Qadis were part of the clergy. However, there were one or two cities ruled by such Qadis, like Tripoli/Trablus-Sham, but they were exceptions. But let me think of other alternatives...