Not being able to scroll the magnified liveview is a lost opportunity, hell I can even do it on my wife's £300 micro four thirds! I wonder if this limitation was known to Leica at the outset or if it crept up on them and bit them on the ass.
That said I still might bite.
Wouldn't get you the 17mm or 24mm shifter/tilter toys, though!
Maybe you should just get a top Canon body and the 17mm and then decide if that's where you want to expand your expenditure? You're going to be on a tripod anyway...
Focussing on one thing and then recomposing doesn't work, as you
already know - it just approximates, but I can't be bothered to go through all the geometry again for others who haven't figured it out for themselves yet.
I never owned a Leica, even when I was working and it would have been no problem; I was often tempted, but the moment I thought about being deprived of a ground glass, 100% coverage of field of view and split image, or ruled lines...
I can't say for sure, of course, but I figure you would be much the same.