Why pause? Think of runescape in a way.. you can help your friends do some quest trade items with eachother things like that I see your point aswell and healing you don't have to pause it could be kinda like wow but not there's a 1000 different ways to do it. They could even have new quests for multiplayer that you can only do on multiplayer .. and say player A Is done with everything all that matters is for player B than because player b would get the help he or she needs it wouldn't have to be a massive mmo just a Maybe 4 player thing dosnt even have to be. 4 player just. 2 or maybe more.. skyrim has the potential it would be amazing .. I forgot what the game is called but I remember pausing the game and it would still be on.. do you get what I'm trying to say? It would be like wow . But just skyrim style
What your asking for is a complete re-design...
Again....
wait for The Elder Scrolls Online if you want multi-player. Skyrim was never designed as nor intended to be an MMO. Runescape was designed from the start as a multiplayer experience. As was WOW. As is any other MMO. From the beginning stages of planning, they had multiplayer in mind.
Bethesda would have to rescript the entire game to accommodate multiplayer. Just think about the opening scene and imagine how different and difficult that would be.
Player A... I'll follow Ralof.
Player B... Nah, I like Hadvar.
Now what?
There are cave-ins and different elements that would block the other player from advancing. Think of the scene with the Torturer. How would that play out now if one is Stormcloak and the other is Empire? Would we then fight to the death?
If both were forced to the same path, once you finally exit Helgen via the cave, now what? One guy goes to Riverwood to further the Main Quest while the other starts heading off to Winterhold because he wants to be a Mage. Player A advances the Main Quest, but leaves Player B behind.
It's not as simple as you make it out to be.
How can I NOT pause in combat to access my menus? I can't move while my menus are open can I? So I'm to stand there, taking a beating while I navigate through the menus to find my healing potions?
MMOs work on the PC because there are multitudes of hotkey options. While this may work on the PC-version of Skyrim, what about the Consoles? I'm pretty sure that the vast majority of Skyrim players are console players. Why re-design the game with only maybe 20% of users taking advantage?
Consider scalable enemies also, what if one player is significantly higher than the other? You'd have crypts full of Draugr Deathlords attacking the low level player.
While it's nice to sit and dream about what could be, take some time to think about what you're really asking and take a bit more time to think about how it would actually be implemented.