About the wide angle.
This ismsimply explained, the larger the sensor gets the more mm's will be called wide angle.
On a 645 for example the 80mm is about equal as the 50mm on a FF DSLR, however on a 6x7 like the Mamiya rx67 it goes up even more app 110-120.
When you use a digital back remember that almost all also have a crop factor.
On the 645 this can range from 1.1 for the leaf aptusII5-7 to 1.4 (or more), when placing the same back on the RZ you will get a huge crop, meaning to get the same angle of view on the RZ you will need the same mm lens as on the 645 although the image on the viewfinder is huge, that's why you have to use crop marks on your glass.
About scanning film.
I'm using the v700 with a better scanning tranny (the normal tranny is almost useless if you want quality), I don't know where you got the idea it wipes the floor with the 5d but that is not true.
When I scan on the best possible way, with a good negative the results are stunning, when downsizing and comparing sharpness the REAL detail will clock in at about 16mp, also remember that film is a totally different animal than a digital sensor. With digital the sensor is 100% flat, film never is, meaning if you want real sharpness nothing beats the digital. If you want dynamic range a very well lit shot on film will not get close to a DSLR with most (if not all color film) on some b&w films it's very close or maybe slightly better.
Don't get me wrong I LOVE shooting film but more for creative issues.
Love to just destroy a film by lying it in the sun before shooting, or using expired film, it can get you some wonderful results which you can try to minic in Photoshop later on.
However scanning is a pain in the so called you know what
Prepare for some dust removal after scanning, prepare for spending several hours fine tuning the tranny to get the perfect scan, and get newton glass to sandwich your negatives when they are curved.
Film for fun or creative process is fun, otherwise stick with a 5d mkII.
And when you outgrow that system go for MF but only if you can't do with the 5dMKII what you want.
MF is wonderful but it's not a miracle camera that will transform you into a better photographer, in the end it's about the image, the camera is just a tool.
Use MF when you want less DOF in your shot, use a DSLR when you need more for example.
I would never ever sell my DSLR, but also probably never will sell my MF, horses for courses with the exception that my 5dmkII does everything really well, and my MF does somethings excellent