I tried a temporary fix for that cloak armor enchant bug -- guess it didn't quite work. I'm simultaneously working on brand new armory parsing code that will handle it for certain, but it will be another week or so before that code can go live. I'll see if I can quickly fix that cloak enchant issue in the short term.
The default weight on armor is already pretty high... recall that we don't multiply it at all to even it up with the item budget of other stats, the weight is for 1 point of armor compared to 1 point of strength (or whatever other stat). That said, if it needs to be higher, that's fine by me!
Yeah stamina I just guessed -- I'll keep an eye on the tests and all that Theck and others are running as MoP gets closer. It has always been a somewhat "problematic" stat to weight, since it is somewhat independent of the other stats.
I hope to finish our coding changes for MoP with at least a week to spare before release, during which I plan to revive our tanking simulator that is used to tweak tanking stats. It only worked for bears in cataclysm, but I want to extend it to all tank classes in MoP.