I would really love the ability to "merge" two interfaces in the form of either it being part of the normal tools, or maybe a separate utility? This would be awesome for things like when you replace a router off-lease and it forces you to change what interface it was on. Or even if you do something like go from a single T1 to a multilink bonded couple of T1's. Its seems so wasteful to just discard that old data when changes happen...