well, dragon knight saga isnt really meant to be played multi... it kind of destroys the lore, and there isnt any kind of cooperation needed anywhere...
For Original Sin, the cooperation is really awesome as it takes a load of your shoulders and is actually pretty interesting (despite the few bugs you could find, such as the loss of control of your characters, which can only be fixed by reloading)
But i still think that being able to bring in your own character would be awesome
