A set of inexpensive/less expensive rims with your froad tires mounted up for froading, and keeping your road tires on the rims you have is a good compromise if you are willing to take off and put on for every trip...if there are not too many trips....once a month or something...its not that big a deal.
You don't have to do anything except take off the road set, and put on the froad set (Reverse when home again....)
Alignment, etc...should be fine. (Unless while of road you hit some nasty thing that knocked your suspension for a loop, etc.)
If you get a second set for off road...get 5...if you needed MT's to get into trouble in the first place...you'll need them to get back out too...Blow out the fourth MT...leaving three MT's, and a Longtrail....can make it a VERY long trail.
Not to mention the fun your ABS, etc. will have dealing with three large tires and one puny tire, on the way home in the rain, snow...etc.