Again I have to ask if you've had the chance to shoot such a system.
Your current workflow was developed around the capabilities of your current platform.
It is possible that with medium format you'll still find you want to take a dozen loose shots with three exposures each,
and do all your work in post to blend and merge them. But you'd be the exception not the rule.
Most users (even those very heavily focused on quality) are very happy with the quality from a single capture, or at most a 2 or 3 image stitch with no exposure blending.
Until you've taken some real world images with a LFD platform I would not make assumptions about how you will use it.
One of the advantages of stitching is using only one lens... and having to carry only one lens (and maybe another for backup)
The tendency is toy use those lenses that on all systems tend to be the best and that is short to medium telephoto.
These lenses tend to have the best corner to corner resolution in particular with reflex cameras.
For this reason the amount of shots taken is largely determined by what angle of view you want for the final shot.
There are also considerations to be made regarding how much time can be taken for the overall shot.
That said the IQ180 is still the best choice as far as ultimate resolution goes for single shot photos.
As far as the need or not for exposure blending there is no advantage with a MFD back compared to
many DSLRs. These days there are quite a few with as high dynamic range, even budget cameras with smaller sensors.
That said the need for exposure blending on very wide panos is more common than with single shot work.
This is because a pano can go from pointing almost at the sun to the complete opposite side of the sky.
Panos are not a total replacement for MFD and MFD is not a replacement for panos.