XE-1 drawbacks vs X100?

I love shooting my X100 using the EVF with auto-ISO and a lower limit shutter speed set.  I also love having the built in ND filter.  My understanding is that the auto-ISO feature of the XE-1 lacks the option to set a lower limit shutter speed setting.  Is this true?  If so perhaps it will be added latter but that is a huge downside for me.  Why oh why would it be this way?  Additionally, although less troubling, I am pretty sure there would be no built in ND filter (as this is built in the lens?) when using an M-mount lens on the XE-1?

Thanks for any verification of these points!