Seeing your pic reminded me.... 

A while back I believe someone posted on AgTalk about a mower that was build offset.  You could mow banks and still have the tractor on the level, and not on the side of the bank.  That seems like a good idea here.  Not sure these guys would have been interested hearing about it, but that idea crossed my mind when I saw your pics.

If someone knows the brand of those mowers, maybe they want to post it here again for everyone interested can see it.